electrum: when broadcasting transaction, error message from server is displayed as is

EDIT2: To users: when you broadcast a transaction, servers can tell you about errors with the transaction. In Electrum versions before 3.3.3, this error is arbitrary text, and what’s worse, it is HTML/rich text (as that is the Qt default). So the server you are connected to can try to trick you by telling you to install malware (disguised as an update). You should update Electrum from the official website so that servers can no longer do this to you. If you see these messages/popups, just make sure you don’t follow them and that you don’t install what they tell you to install. The messages are just messages, they cannot hurt you by themselves.

TL;DR: There is an ongoing attack against users where servers raise exceptions when a client broadcasts a transaction; in this case the error text is displayed as is in the client GUI. The attacker has spawned lots of servers on different /16 IPv4s to increase his chances of being connected to. The error messages are trying to get the user to download and install malware (disguised as updated versions of electrum).

In relation to https://github.com/spesmilo/electrum/issues/4953, we were privately sent a screenshot that was apparently floating around a German chat room (on 2018-12-21).

broadcast_transaction

There wasn’t really any extra information given, however most likely the following happened:

user was using legitimate electrum client
connected to an electrum server operated by the attacker
user tried to broadcast a txn
server replied with an error containing the above rich text message

https://github.com/spesmilo/electrum/blob/b491a30dd9f550ab2f335ae88889c910125d4559/electrum/network.py#L734-L741

To make the attack more effective, the attacker is creating lots of servers (sybils), hence increasing the chance a client would connect to him. See this graph on the number of servers hsmiths shared re the peers found by his server: electrumx_peers-week

At the very least, the message should not be displayed as rich text. It is untrusted input afterall… We should also show some additional explanatory text at the beginning (prepend something).

For context, this mechanism of the server returning error message text to txn broadcasts is used to display error messages originating from bitcoind, such as low incremental fee or missing inputs, etc. Maybe the server should return error codes (ints) instead, and we could have our own decoding table, but then this would need to be kept in sync with bitcoind… (EDIT3: looked into this more, see https://github.com/spesmilo/electrum/issues/4968#issuecomment-455557296)

Hours after we were sent the screenshot, we silently made mitigations in https://github.com/spesmilo/electrum/commit/5248613e9d7b8b8ec85a1cee897d1901d747f5b4 and https://github.com/spesmilo/electrum/commit/5dc240d4ed39796bec72ac115d920160865b3ec5; and released 3.3.2. This is not a true fix, but the more proper fix of using error codes would entail upgrading the whole federated server ecosystem out there…

We did not publicly disclose this until now, as around the time of the 3.3.2 release, the attacker stopped; however they now started the attack again.

This is how the attack, live as writing this now, looks on 3.3.2: broadcast_transaction_malware2

This is on server plmimservice.bitcoinplug.website on mainnet.

My current server peers on bitcoin mainnet

Host                           Status   TCP   SSL Server             Min  Max  Pruning   Last Good    Last Try Tries               Source IP Address
nl.bitops.me                   good   50001 50002 ElectrumX 1.8.12   1.2  1.4          01h 40m 07s 01h 40m 07s     0                 peer 103.214.4.65
207.154.223.80                 good   50001 50002 ElectrumX 1.2.1    0.9  1.2          01h 50m 14s 01h 50m 14s     0                 peer 207.154.223.80
hsmiths4fyqlw5xw.onion         good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 17m 08s 02h 17m 14s     0                 peer
y4td57fxytoo5ki7.onion         good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 17m 18s 02h 17m 24s     0                 peer
4cii7ryno5j3axe4.onion         good   50001       ElectrumX 1.3.1    0.9  1.2          02h 17m 27s 02h 17m 29s     0                 peer
luggscoqbymhvnkp.onion         good      80       ElectrumX 1.8.7    1.1  1.4          02h 17m 28s 02h 17m 32s     0                 peer
qtornadoklbgdyww.onion         good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 17m 57s 02h 18m 01s     0                 peer
ndndword5lpb7eex.onion         good   50001       ElectrumX 1.8.12   1.2  1.4          02h 18m 09s 02h 18m 14s     0                 peer
electrum-server.ninja          good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 19m 31s 02h 19m 33s     0                 peer 220.233.178.199
yuio.top                       good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 19m 33s 02h 19m 35s     0                 peer 118.86.185.36
139.162.14.142                 good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 19m 37s 02h 19m 38s     0                 peer 139.162.14.142
electrumx.ddns.net             good   50001 50002 ElectrumX 1.8.7    1.1  1.4          02h 19m 44s 02h 19m 45s     0                 peer 169.0.147.67
electrum.hsmiths.com           good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 19m 50s 02h 19m 51s     0                 peer 76.174.26.91
orannis.com                    good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 19m 51s 02h 19m 52s     0                 peer 50.35.67.146
enode.duckdns.org              good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 19m 52s 02h 19m 53s     0                 peer 75.159.6.167
electrum.leblancnet.us         good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 19m 52s 02h 19m 53s     0                 peer 205.197.210.32
dragon085.startdedicated.de    good         50002 ElectrumX 1.8.12   1.2  1.4          02h 19m 54s 02h 19m 55s     0                 peer 69.64.46.27
electrumx.bot.nu               good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 19m 56s 02h 19m 57s     0                 peer 173.91.90.62
technetium.network             good         50002 ElectrumX 1.8.7    1.1  1.4          02h 19m 57s 02h 19m 58s     0                 peer 96.27.8.242
E-X.not.fyi                    good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 19m 57s 02h 19m 58s     0                 peer 170.130.28.174
us.electrum.be                 good   50001 50002 ElectrumX 1.8.7    1.1  1.4          02h 19m 58s 02h 19m 59s     0                 peer 208.110.73.107
electrum.coinucopia.io         good   50001 50002 ElectrumX 1.4.3    1.0  1.2          02h 20m 01s 02h 20m 01s     0                 peer 67.205.187.44
elec.luggs.co                  good           443 ElectrumX 1.8.7    1.1  1.4          02h 20m 05s 02h 20m 06s     0                 peer 95.211.185.14
electrum2.eff.ro               good   50001 50002 ElectrumX 1.8.5    1.1  1.4          02h 20m 06s 02h 20m 06s     0                 peer 195.135.194.3
AZZARITA.hopto.org             good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 08s 02h 20m 08s     0                 peer 2.236.8.149
electrumx.soon.it              good   50001 50002 ElectrumX 1.8.11   1.2  1.4          02h 20m 08s 02h 20m 09s     0                 peer 79.11.31.76
electrumx.ftp.sh               good         50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 09s 02h 20m 09s     0                 peer 213.246.56.95
81-7-13-84.blue.kundencontroll good         50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 09s 02h 20m 09s     0                 peer 81.7.13.84
electrum.petrkr.net            good   50001 50002 ElectrumX 1.4.3    1.0  1.2          02h 20m 09s 02h 20m 09s     0                 peer 213.168.187.27
fedaykin.goip.de               good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 09s 02h 20m 10s     0                 peer 109.192.105.174
81-7-16-182.blue.kundencontrol good         50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 10s 02h 20m 10s     0                 peer 81.7.16.182
elx01.knas.systems             good   50001 50002 ElectrumX 1.8.4    1.1  1.4          02h 20m 10s 02h 20m 10s     0                 peer 83.233.65.59
bitcoin.grey.pw                good   50001 50002 ElectrumX 1.8.7    1.1  1.4          02h 20m 10s 02h 20m 10s     0                 peer 173.249.8.197
electrum.festivaldelhumor.org  good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 10s 02h 20m 11s     0                 peer 207.180.219.223
tardis.bauerj.eu               good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 10s 02h 20m 11s     0                 peer 51.15.138.64
electrum.anduck.net            good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 11s 02h 20m 11s     0                 peer 62.210.6.26
ndnd.selfhost.eu               good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 11s 02h 20m 11s     0                 peer 87.156.193.92
qmebr.spdns.org                good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 11s 02h 20m 11s     0                 peer 92.116.97.34
bitcoins.sk                    good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 11s 02h 20m 11s     0                 peer 46.229.238.187
tomscryptos.com                good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 11s 02h 20m 11s     0                 peer 95.216.28.117
ulrichard.ch                   good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 11s 02h 20m 11s     0                 peer 151.248.186.86
electrum.villocq.com           good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 11s 02h 20m 12s     0                 peer 78.143.214.223
b.ooze.cc                      good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 12s 02h 20m 12s     0                 peer 145.239.252.207
vmd27610.contaboserver.net     good         50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 12s 02h 20m 12s     0                 peer 173.249.48.200
electrum.nute.net              good         50002 ElectrumX 1.3      0.9  1.2          02h 20m 12s 02h 20m 12s     0                 peer 37.187.141.73
currentlane.lovebitco.in       good   50001 50002 ElectrumX 1.8.7    1.1  1.4          02h 20m 12s 02h 20m 12s     0                 peer 88.198.91.74
rbx.curalle.ovh                good         50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 12s 02h 20m 12s     0                 peer 176.31.252.219
185.64.116.15                  good   50001 50002 ElectrumX 1.8.9    1.1  1.4          02h 20m 12s 02h 20m 13s     0                 peer 185.64.116.15
13.80.67.162                   good   50001 50002 ElectrumX 1.4.3    1.0  1.2          02h 20m 12s 02h 20m 13s     0                 peer 13.80.67.162
kirsche.emzy.de                good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 13s 02h 20m 13s     0                 peer 78.47.61.83
vmd30612.contaboserver.net     good         50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 13s 02h 20m 13s     0                 peer 173.212.249.224
electrum.vom-stausee.de        good   50001 50002 ElectrumX 1.3.1    0.9  1.2          02h 20m 13s 02h 20m 13s     0                 peer 37.59.46.112
fn.48.org                      good   50003 50002 ElectrumX 1.8.7    1.1  1.4          02h 20m 13s 02h 20m 13s     0                 peer 5.79.90.70
electrum.taborsky.cz           good         50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 13s 02h 20m 13s     0                 peer 37.205.8.78
e-1.claudioboxx.com            good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 13s 02h 20m 13s     0                 peer 37.61.209.146
e-2.claudioboxx.com            good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 14s 02h 20m 14s     0                 peer 37.61.209.147
btc.cihar.com                  good   50001 50002 ElectrumX 1.8.7    1.1  1.4          02h 20m 14s 02h 20m 14s     0                 peer 78.46.177.74
dedi.jochen-hoenicke.de        good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 14s 02h 20m 14s     0                 peer 88.198.39.205
hetzner01.fischl-online.de     good         50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 14s 02h 20m 14s     0                 peer 5.9.124.124
electrum.be                    good   50001 50002 ElectrumX 1.8.7    1.1  1.4          02h 20m 14s 02h 20m 14s     0                 peer 88.198.241.196
electrum.qtornado.com          good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 20m 15s 02h 20m 15s     0                 peer 88.99.162.199
bitcoin.corgi.party            good   50001 50002 ElectrumX 1.8.12   1.2  1.4          02h 30m 09s 02h 30m 09s     0                 peer 176.223.139.65
mooo.not.fyi                   good   50011 50012 ElectrumX 1.8.12   1.2  1.4          02h 38m 52s 02h 38m 53s     0                 peer 71.239.40.8
2AZZARITA.hopto.org            good   50001 50002 ElectrumX 1.8.12   1.2  1.4          03h 07m 03s 03h 07m 03s     0                 peer 173.212.253.26
tpslocalserver12.cryptoplayer. good   50001 50002 ElectrumX 1.8.12   1.2  1.4          04h 28m 07s 04h 28m 09s     0                 peer 128.199.223.21
62.80.227.49                   good   50001 50002 ElectrumX 1.8.12   1.2  1.4          04h 30m 12s 04h 30m 12s     0                 peer 62.80.227.49
ozahtqwp25chjdjd.onion         good   50001 50002 ElectrumX 1.8.12   1.2  1.4          04h 46m 27s 04h 46m 34s     0                 peer
sysdump112.bitcoinplug.website good   50001 50002 ElectrumX 1.8.12   1.2  1.4          04h 49m 49s 04h 49m 50s     0                 peer 128.199.223.23
prodcics12.imaginarycoin.info  good   50001 50002 ElectrumX 1.8.12   1.2  1.4          04h 50m 00s 04h 50m 02s     0                 peer 128.199.223.22
sysadmin12.23734430190.pro     good   50001 50002 ElectrumX 1.8.12   1.2  1.4          04h 50m 04s 04h 50m 05s     0                 peer 128.199.225.8
computer12.krypto-familar.fun  good   50001 50002 ElectrumX 1.8.12   1.2  1.4          04h 50m 23s 04h 50m 25s     0                 peer 128.199.225.13
gregoire12.mldlab-works.space  good   50001 50002 ElectrumX 1.8.12   1.2  1.4          04h 50m 54s 04h 50m 55s     0                 peer 128.199.218.24
quaternion.tech                good   50001 50002 ElectrumX 1.8.12   1.2  1.4          04h 58m 38s 04h 58m 39s     0                 peer 104.244.222.239
btc.smsys.me                   good           995 ElectrumX 1.8.12   1.2  1.4          04h 59m 50s 04h 59m 52s     0                 peer 50.198.167.205
helicarrier.bauerj.eu          good   50001 50002 ElectrumX 1.8.7    1.1  1.4          05h 00m 12s 05h 00m 12s     0                 peer 178.32.88.133
bfav33xnleliriow.onion         good   50001 50002 ElectrumX 1.8.12   1.2  1.4          05h 26m 47s 05h 26m 52s     0                 peer
128.199.223.10                 good   50001 50002 ElectrumX 1.8.12   1.2  1.4          05h 43m 10s 05h 43m 11s     0                 peer 128.199.223.10
utilities12.pebwindkraft.space good   50001 50002 ElectrumX 1.8.12   1.2  1.4          05h 48m 13s 05h 48m 14s     0                 peer 52.221.249.16
security12.cryptoplayer.fun    good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 04m 33s 06h 04m 36s     0                 peer 13.229.97.230
museadmin12.imaginarycoin.info good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 04m 55s 06h 04m 56s     0                 peer 3.0.98.224
qtmhhttp12.mldlab-works.space  good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 05m 17s 06h 05m 19s     0                 peer 13.229.197.132
qautprof12.coinucopiaspace.xyz good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 05m 38s 06h 05m 39s     0                 peer 54.255.206.0
politcally12.23734430190.pro   good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 07m 29s 06h 07m 30s     0                 peer 13.229.130.59
wlseuser12.bitcoinplug.website good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 08m 07s 06h 08m 08s     0                 peer 18.136.203.167
pacslinkip12.krypto-familar.fu good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 08m 10s 06h 08m 11s     0                 peer 3.0.139.42
wireless12.bitquantum.space    good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 08m 18s 06h 08m 19s     0                 peer 13.229.224.194
walle.dedyn.io                 good         50002 ElectrumX 1.8.12   1.2  1.4          06h 25m 12s 06h 25m 12s     0                 peer 79.148.156.226
daedalus.bauerj.eu             good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 45m 56s 06h 45m 56s     0                 peer 5.230.24.38
db2admin1.krypto-familar.fun   good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 49m 42s 06h 49m 44s     0                 peer 172.104.57.12
oraprobe.23734430190.pro       good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 54m 09s 06h 54m 11s     0                 peer 45.76.70.111
videouser.bitcoinplug.website  good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 54m 44s 06h 54m 47s     0                 peer 108.61.218.93
vcoadmin.23734430190.pro       good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 54m 46s 06h 54m 49s     0                 peer 66.42.103.16
openspirit.cryptoplayer.fun    good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 55m 31s 06h 55m 32s     0                 peer 45.77.241.145
security1.bitcoinplug.website  good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 55m 43s 06h 55m 45s     0                 peer 103.3.63.9
anonymous.bitcoinplug.website  good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 55m 47s 06h 55m 49s     0                 peer 66.42.104.125
adminstat.imaginarycoin.info   good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 55m 48s 06h 55m 50s     0                 peer 45.32.101.251
siteminder.23734430190.pro     good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 56m 11s 06h 56m 14s     0                 peer 45.76.70.99
operatns.imaginarycoin.info    good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 56m 26s 06h 56m 27s     0                 peer 207.148.75.252
username.cryptoplayer.fun      good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 56m 26s 06h 56m 27s     0                 peer 45.77.242.185
lessonuser2.cryptoplayer.fun   good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 56m 32s 06h 56m 33s     0                 peer 139.180.132.139
adminstat1.bitquantum.space    good   50001 50002 ElectrumX 1.8.12   1.2  1.4          06h 57m 11s 06h 57m 12s     0                 peer 172.104.164.217
btc.xskyx.net                  good   50001 50002 ElectrumX 1.8.7    1.1  1.4          08h 01m 13s 08h 01m 13s     0                 peer 185.183.158.170
oaihub902.imaginarycoin.info   good   50001 50002 ElectrumX 1.8.12   1.2  1.4          09h 04m 39s 09h 04m 40s     0                 peer 54.169.204.38
username.bitcoinplug.website   good   50001 50002 ElectrumX 1.8.12   1.2  1.4          09h 05m 08s 09h 05m 09s     0                 peer 13.229.98.142
topicres.imaginarycoin.info    good   50001 50002 ElectrumX 1.8.12   1.2  1.4          09h 05m 14s 09h 05m 15s     0                 peer 13.250.37.215
scientific.23734430190.pro     good   50001 50002 ElectrumX 1.8.12   1.2  1.4          09h 05m 29s 09h 05m 30s     0                 peer 54.169.192.215
security.cryptoplayer.fun      good   50001 50002 ElectrumX 1.8.12   1.2  1.4          09h 05m 32s 09h 05m 33s     0                 peer 3.0.59.204
plmimservice.bitcoinplug.websi good   50001 50002 ElectrumX 1.8.12   1.2  1.4          09h 05m 41s 09h 05m 42s     0                 peer 18.136.102.143
readonly.23734430190.pro       good   50001 50002 ElectrumX 1.8.12   1.2  1.4          09h 05m 58s 09h 06m 00s     0                 peer 54.255.195.58
qlpinstall.krypto-familar.fun  good   50001 50002 ElectrumX 1.8.12   1.2  1.4          09h 06m 04s 09h 06m 06s     0                 peer 3.0.19.36
superman.cryptoplayer.fun      good   50001 50002 ElectrumX 1.8.12   1.2  1.4          09h 06m 15s 09h 06m 16s     0                 peer 54.169.53.21
lucent01.23734430190.pro       good   50001 50002 ElectrumX 1.8.12   1.2  1.4          09h 08m 00s 09h 08m 01s     0                 peer 52.74.115.7
erbium1.sytes.net              good   50001 50002 ElectrumX 1.8.12   1.2  1.4          09h 58m 02s 09h 58m 03s     0                 peer 46.246.49.225
superuser.23734430190.pro      good   50001 50002 ElectrumX 1.8.12   1.2  1.4          12h 00m 33s 12h 00m 34s     0                 peer 54.254.191.195
VPS.hsmiths.com                good   50001 50002 ElectrumX 1.8.12   1.2  1.4          12h 14m 29s 12h 14m 31s     0                 peer 51.15.77.78
electrum2.villocq.com          good   50001 50002 ElectrumX 1.8.5    1.1  1.4          12h 30m 08s 12h 30m 09s     0                 peer 88.81.143.198
electrumx.schmoock.net         good   50001 50002 ElectrumX 1.8.12   1.2  1.4          17h 44m 18s 17h 44m 18s     0                 peer 46.4.92.21
e.keff.org                     good   50001 50002 ElectrumX 1.8.12   1.2  1.4          19h 07m 57s 19h 07m 57s     0                 peer 194.71.109.91
electrum3.everynothing.net     good   50001 50002 ElectrumX 1.8.12   1.2  1.4          20h 59m 59s 21h 00m 00s     0                 peer 198.23.152.179
electrumx.strangled.net        good         50002 ElectrumX 1.8.12   1.2  1.4          22h 49m 55s 22h 49m 57s     0                 peer 69.30.215.42
62.210.170.57                  good         50002 ElectrumX 1.8.12   1.2  1.4          23h 02m 38s 23h 02m 38s     0                 peer 62.210.170.57
s7clinmo4cazmhul.onion         good   50001       ElectrumX 1.8.12   1.2  1.4          23h 21m 28s 23h 21m 35s     0                 peer
bitcoin-server.cf              good         50002 ElectrumX 1.8.12   1.2  1.4          23h 21m 46s 23h 21m 47s     0                 peer 185.181.61.140
n3o2hpi5xnf3o356.onion         stale  50001 50002 ElectrumX 1.3      0.9  1.2           1d 02h 02m 01h 02m 30s     4                 peer
electrum.coineuskal.com        stale  50001 50002 ElectrumX 1.3      0.9  1.2           1d 02h 09m 01h 09m 57s     4                 peer 34.207.56.59
54.179.187.114                 stale  50001 50002 ElectrumX 1.8.12   1.2  1.4           1d 02h 25m         34s     5                 peer 54.179.187.114
bauerjhejlv6di7s.onion         stale  50001 50002 ElectrumX 1.8.7    1.1  1.4           1d 04h 47m 04h 55m 27s     1                 peer
54.251.183.105                 stale  50001 50002 ElectrumX 1.8.12   1.2  1.4           1d 09h 28m 04h 22m 43s     6                 peer 54.251.183.105
159.65.137.67                  stale  50001 50002 ElectrumX 1.8.12   1.2  1.4           1d 09h 41m 04h 41m 22s     6                 peer 159.65.137.67
128.199.206.38                 stale  50001 50002 ElectrumX 1.8.12   1.2  1.4           2d 01h 41m 04h 34m 48s     8                 peer 128.199.206.38
81-7-10-251.blue.kundencontrol stale        50002 ElectrumX 1.8.12   1.2  1.4           3d 12h 00m 17h 40m 09s     9                 peer 81.7.10.251
electrum.mindspot.org          stale        50002 ElectrumX 1.8.12   1.2  1.4           4d 01h 39m  1d 07h 19m     9                 peer 172.103.153.90
84.197.110.145                 stale  50001 50002 ElectrumX 1.8.12   1.2  1.4           4d 12h 58m  1d 18h 38m     9                 peer 84.197.110.145
node.ispol.sk                  stale  50001 50002 ElectrumX 1.3+     0.9  1.2          10d 00h 40m  9d 00h 49m     1                 peer 193.58.196.212
3smoooajg7qqac2y.onion         stale  50001 50002 ElectrumX 1.8.12   1.2  1.4          15d 23h 39m 14d 22h 59m     3                 peer
such.ninja                     never  50001 50002 ElectrumX 1.2      0.9  1.1                Never     07m 51s     2       163.172.61.154 163.172.61.154
ip120.ip-54-37-91.eu           never  50001 50002 ElectrumX 1.2.1    0.9  1.1                Never     08m 38s     1         54.37.91.120 54.37.91.120
electrum.dk                    never  50001 50002 ElectrumX 1.2      0.9  1.1                Never 13d 09h 00m     3        92.246.24.225 92.246.24.225
13.250.108.34                  never  50001 50002 ElectrumX 1.8.12   1.2  1.4                Never 10d 03h 50m     2        13.250.108.34 13.250.108.34
ip119.ip-54-37-91.eu           never  50001 50002 ElectrumX 1.2.1    0.9  1.1                Never     15m 04s     2         54.37.91.119 54.37.91.119
165.227.22.180                 never  50001 50002 ElectrumX 1.2      0.9  1.1                Never     09m 46s     1       165.227.22.180 165.227.22.180
104.250.141.242                never        50002 ElectrumX 1.2      0.9  1.1                Never     16m 52s     2      104.250.141.242 104.250.141.242
ip239.ip-54-36-234.eu          never  50001 50002 ElectrumX 1.2.1    0.9  1.1                Never     17m 24s     2        54.36.234.239 54.36.234.239
ip101.ip-54-37-91.eu           never  50001 50002 ElectrumX 1.2.1    0.9  1.1                Never     05m 10s     2         54.37.91.101 54.37.91.101
xray587.startdedicated.de      bad          50002 ElectrumX 1.8.12   1.2  1.4              42m 00s     42m 01s     0                 peer 188.138.88.42
electrumx.ga                   bad          50002 ElectrumX 1.8.12   1.2  1.4          01h 20m 11s 01h 20m 11s     0                 peer 178.32.223.22
7jwtirwsaogb6jv2.onion         bad    50001 50002 ElectrumX 1.3+     0.9  1.2          10d 00h 39m  9d 00h 34m     2                 peer

Notice there are 7 *.bitcoinplug.website domains. There are 6 *.imaginarycoin.info domains. There are 9 *.23734430190.pro domains. There are 7 *.cryptoplayer.fun domains. There are 4 *.krypto-familar.fun domains.

(EDIT1: noticed at 2018-12-27 14:48 UTC that these domains are no longer DNS resolving)

@ecdsa @ysangkok

EDIT4: For longer term resolution of this issue, see https://github.com/spesmilo/electrum/issues/4968#issuecomment-455557296 and https://github.com/spesmilo/electrum/pull/5011

About this issue

Original URL
State: closed
Created 6 years ago
Reactions: 31
Comments: 70 (29 by maintainers)

Links to this issue

Commits related to this issue

Anti-Phishing: Suppress all server messages from appearing in GUI and instead parse & translate them. (#1076) This is in response to the recent sybil phishing attack discussed here in this Electrum t... — committed to Electron-Cash/Electron-Cash by cculianu 6 years ago
Mitigations for upstream issue https://github.com/spesmilo/electrum/issues/4968 — committed to litecoincash-project/electrum-lcc by l0x 5 years ago
Minimum supported protocol version is 1.1 — committed to kyuupichan/electrumx by deleted user 6 years ago
Remove Electrum 3.1.3 (vulnerable to phishing attacks) https://github.com/spesmilo/electrum/issues/4968 Signed-off-by: Kristaps Kaupe <kristaps@blogiem.lv> — committed to kristapsk/gentoo by kristapsk 5 years ago

Most upvoted comments

In Bitcoin Core we have been fairly aggressive about not displaying human readable text sourced from the network (peers, transactions, or blocks) to users specifically because of the potential for this kind of attack. I have previously recommended everyone else do the same, and I would continue to recommend it here.

+44

gmaxwell on Dec 27, 2018

The safe way is to get the error code from servers and keep the error chart table at electrum official website. Whenever one gets an error, just go to electrum website and find out what the error code means.

The sane thing is to have the decoding table in the client…

+15

SomberNight on Dec 27, 2018

Wouldn’t it better if the error message contained a hint that the following text came from a 3rd party electrum-server and should therefore never prompt you to download/update anything (or at least a hint to check electrum.org for updates if you ever want such a message about real updates)?

I have no idea how many people are able to read the HTML message and still fall for it, but I don’t think it can do any harm. Also the attack could work without HTML and I could see people falling for it even with the current fix.

+13

takedown000 on Dec 27, 2018

The safe way is to get the error code from servers and keep the error chart table at electrum official website. Whenever one gets an error, just go to electrum website and find out what the error code means.

+11

RB3rg on Dec 27, 2018

We need to teach more people how to check pgp signatures.

Ancapzin on Dec 27, 2018

When you download the fake client they must get your seed/password somehow. I wiped electrum files then restore the wallet from seed and put a very small amount in there an let it sit. They just emptied the wallet again about 30 mintues ago.

onyx823 on Dec 27, 2018

And years later people are still being effected by this bug to the tune of millions of dollars. This is insane, and you should be liable for the damages here. Rendering arbitrary html on an error update page for a financial tool is not ok. I’ll be send this to my local authorities.

wbronitsky on Dec 22, 2020

waiting for network to get connected...
asking server electrum.qtornado.com:50002:s for its peers
got 113 servers
contacting 109 servers
connected to 85 servers
85 answers
Results: attacker 25, honest 60
Attacker servers: [
  'gregoire12.mldlab-works.space:50002:s',
  'readonly.23734430190.pro:50002:s',
  'wireless12.bitquantum.space:50002:s',
  'superuser.23734430190.pro:50002:s',
  'pacslinkip12.krypto-familar.fun:50002:s',
  'topicres.imaginarycoin.info:50002:s',
  'wlseuser12.bitcoinplug.website:50002:s',
  'operatns.imaginarycoin.info:50002:s',
  'superman.cryptoplayer.fun:50002:s',
  'lucent01.23734430190.pro:50002:s',
  'qtmhhttp12.mldlab-works.space:50002:s',
  'plmimservice.bitcoinplug.website:50002:s',
  'username.cryptoplayer.fun:50002:s',
  'qlpinstall.krypto-familar.fun:50002:s',
  'adminstat.imaginarycoin.info:50002:s',
  'lessonuser2.cryptoplayer.fun:50002:s',
  'utilities12.pebwindkraft.space:50002:s',
  'openspirit.cryptoplayer.fun:50002:s',
  'qautprof12.coinucopiaspace.xyz:50002:s',
  'prodcics12.imaginarycoin.info:50002:s',
  'vcoadmin.23734430190.pro:50002:s',
  'siteminder.23734430190.pro:50002:s',
  'videouser.bitcoinplug.website:50002:s',
  'anonymous.bitcoinplug.website:50002:s',
  'oraprobe.23734430190.pro:50002:s'
]

SomberNight on Dec 27, 2018

Given these types of attacks, might it be prudent to ensure that all official git release tags be signed by the committer as a condition of becoming an offical release tag?

Tags 3.3.4, 3.3.3, 3.3.2 and 3.3.1 are all unsigned.

Luckily commit:b085d7c (v3.3.3) is signed, but commit:87c596f (v3.3.4), commit:30845ee (v3.3.2) and commit:85b7129 (v3.3.1) are not.

I would think having the tag signed would be a minimum, since the process could happen independent of whether or not the final commit was signed. It may not always be obvious what the last commit of a release will be.

brianddk on May 1, 2019

How about a Show details... button, which only shows the error details after you click it?

It’s not a true fix at all, but it might make the social engineering less effective.

Error codes are good too. How about an option in settings to display detailed error messages, so that users need to go out of their way to see them?

zakurai on Dec 27, 2018

Perhaps. But the fact that the official client sent me to a phishing website is absurd. The client itself told me to go to electrumpal and update. I sent a not insubstantial amount of money to some rando without my knowledge.

On Jun 20, 2019, at 5:55 AM, ghost43 notifications@github.com wrote:

They could enforce PGP signatures on the messages and embed the corresponding public key into future builds. The the broadcast messages could have a verified by @spesmilo or unverified moniker on it.

The client (since 3.3.3) only displays error messages from a hardcoded-in-client set. The server still sends arbitrary messages (see referenced links as to why) and then the client matches them with a long list of regexes, to one of the hardcoded error messages (or “unknown error”). see #4968 (comment) and #5011

— You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.

timbudtwo on Jun 20, 2019

I don’t understand how the official client can feed a user an unofficial link. How can I trust this client ever again when information given to me by it can be controlled by a third party? edit: changed official to unofficial

timbudtwo on Jun 21, 2019

I fell for this and I honestly think you should have screenshots of that error on the main website to alert people or find another way to warn users

webpage_warning

The website has a warning at the top. It has been there since about a day after this issue was opened.

SomberNight on Feb 2, 2019

@adrianTNT see https://github.com/spesmilo/electrum/issues/3198 and https://github.com/spesmilo/electrum/issues/4986#issuecomment-451385953 It’s unrelated to this issue.

SomberNight on Jan 22, 2019

Can someone tell me if this file is legit copy from electrum website ? https://www.virustotal.com/#/file/e5bf6cfcb3181c452ea8f0eaab4539a694a60c45bc6fae8fadbb9eb0ac9b44d3/detection

That is what I get when I download and upload to virustotal website.

electrum wallet scan results

adrianTNT on Jan 22, 2019

We have looked into using error codes/ints but the issue is that not even bitcoind is providing (useful) error codes. To use error codes, either (1) bitcoind would need to be modified, or (2) the electrum server would need to classify/categorise messages into error code buckets.

Closely related to (2), we might as well keep using the current architecture, have the server send arbitrary text to the client, and have the classification done in the client, before displaying anything to the user. This is also what @cculianu did in https://github.com/Electron-Cash/Electron-Cash/pull/1076. i.e. do string matching in the client, and display a message out of a predefined set to the user (with generic fallback). As it stands, we will likely do the same.

This is IMHO an ugly solution but there does not seem to be a better one. bitcoind would need to be modified. PRs for Bitcoin Core that improve the returned errors would be great. Some notes and examples how bitcoind behaves:

the returned error code mostly seems to be one out of four https://github.com/bitcoin/bitcoin/blob/cd42553b1178a48a16017eff0b70669c84c3895c/src/rpc/protocol.h#L54-L57 the most common is -26
there are many errors related to script execution defined at https://github.com/bitcoin/bitcoin/blob/cd42553b1178a48a16017eff0b70669c84c3895c/src/script/script_error.h, all of which seem to give -26 note that the additional “code <int>” part of the error message is also very often “code 64” with only the human readable text differing

some examples

$ bitcoin-cli sendrawtransaction 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
error code: -26
error message:
non-final (code 64)

---

$ bitcoin-cli sendrawtransaction 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
error code: -26
error message:
non-mandatory-script-verify-flag (Non-canonical DER signature) (code 64)

---

$ bitcoin-cli sendrawtransaction 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
error code: -27
error message:
transaction already in block chain

---

$ bitcoin-cli sendrawtransaction 010000000001012005273af813ba23b0c205e4b145e525c280dd876e061f35bff7db9b2e0043640100000000fdffffff0180969800000000001600142698d41038732afb4594d653b38d5708b935e8c402483045022100a201e0a8cab01615bffecfff5b3991cb7df545bfe7cbcef274e3943c37da6dc10220579bc0abf483f875bf6a9cfad7103f0c965a130c7cb337cd09dff2d4b49284b2012103cb3e00561c3439ccbacc033a72e0513bcfabff8826de0bc651d661991ade6171172b1600
error code: -26
error message:
absurdly-high-fee, 90100000 > 10000000 (code 256)

---

$ bitcoin-cli sendrawtransaction 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
error code: -25
error message:
Missing inputs

---

$ bitcoin-cli sendrawtransaction 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
error code: -26
error message:
insufficient fee, rejecting replacement 76be2aed6a10179791fc57abad061a6bbb6ff65f346031f7dd1665fc0ed7edcf, not enough additional fees to relay; 0.00000105 < 0.00000209 (code 66)

---

$ bitcoin-cli sendrawtransaction 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
error code: -22
error message:
TX decode failed

---

$ bitcoin-cli sendrawtransaction 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
error code: -26
error message:
non-mandatory-script-verify-flag (Signature must be zero for failed CHECK(MULTI)SIG operation) (code 64)

SomberNight on Jan 18, 2019

3.3.2 does not show rich text; 3.3.3 fixes the original broadcast_transaction arbitrary text issue; 3.3.4 also catches errors for other lower risk methods (see e.g. https://github.com/spesmilo/electrum/commit/38ab7ee554b89b96c5ac7ea1b83d275d6cdb3cad)

SomberNight on Jul 23, 2019

Is the tweet about 3.3.3 being vunerable true? This thread seems to imply that only 3.3.2 and earlier versions are vulnerable.

brianddk on Jul 22, 2019

https://github.com/grubproject/electrum is gone now

moloko on Feb 12, 2019

Just sent mine in - thanks for the link.

marcobelmonte on Feb 11, 2019

Report Abuse here: https://github.com/contact/report-abuse

cculianu on Feb 11, 2019

Thanks for this. I am complaining to github under the “Report Abuse” section. I suggest you all do the same so that they take down this malware version of Electrum ASAP.

cculianu on Feb 11, 2019

Went to send. Got the phishing alert it could not be sent. Was sent to this URL . I thought if an in app message with GitHub it should be legit. Installed the false client and it never synced. Came back today to try again with a fresh install.

Lost 8k usd @ 2019-02-03 09:32.

Phished from inside the app, what shit.

If Phishers can send a message to legit clients, why not send a proper notice to everyone?

anynamehere on Feb 4, 2019

I can relate to the state of shock. Believe me in my life I’ve also lost many things… not just money. Don’t kill yourself though! Please. I know it doesn’t help much but really you are alive and hopefully healthy. Dying rich men would trade all of their wealth in a heartbeat when they are old just to be healthy again and to live. It’s not worth dying for… No amount of money is.

cculianu on Feb 2, 2019

I fell for this and I honestly think you should have screenshots of that error on the main website to alert people or find another way to warn users. I was lucky I didn’t loose anything the version 4 app the phishers are pushing adds an outgoing transaction maxing your funds. If you try and send a transaction it will try and max the funds. It also wont let you open it without entering your password. I saw this post quickly, uninstalled electrum and downloaded the correct version. I then restored my wallet using the seed phrase and created a new password. Can you or should you change a seed phrase too? I have not had any other alerts from my AV about this so I suspect though it’s malware it’s not adding additional malware and simply uninstalling and reinstalling will address this at a program level.

10771271 on Feb 2, 2019

@metroyanno @Platinumwrist – DO NOT DOWNLOAD FROM THAT LINK. It’s a trojan.

Electrum dev (github version) right now no longer produces error messages form the server – and I believe a new release will come out soon to address this.

For now – switch servers and do not listen download from that link.

cculianu on Feb 1, 2019

Really? Last I looked Electron Cash wasn’t a server.

kyuupichan on Dec 31, 2018

Yea, uh plain text doesn’t fix anything. You have to design for the lowest common denominator of user. (especially if one wants crypto to be adopted broadly…just saying).

You will just get notices like this (made up but just example).

URGENT SECURITY NOTICE

CALL ###-###-#### FOR HELP WITH CRITICAL SECURITY PROBLEMS. YOUR WALLET IS IN DANGER.

It’s hilariously the Windows XP netmsg spam problem. (which made microsoft purge it altogether from later windows).

marekr on Dec 27, 2018

I fell for this… i was in a hurry and half paying attention(i know) but i didn’t even think about getting phished at first since it was a pop up in the real electrum. i should have know better though.

From any info you have, does there seem to be more malicious files attached to ? i.e. should i be reformatting my drive and starting from scratch or does it seem to be a localized attack on BTC?

onyx823 on Dec 27, 2018