TCP-32764

I WILL NOT MANUALLY UPDATE THIS REPOSITORY ANYMORE

If you want to add a router in the list, please make a pull-request, also remember to USE THE POC and paste the result in your pull-request. Telnet clients and other solutions may not be relevant (some false negative / positive reported).

Some random code/data about the backdoor I found in my Linksys WAG200G (TCP/32764).

The backdoor may be present in other hardware, I'll update this readme accordingly. :)

Possible fix :

• if it's listening on the internet: add a firewall rule in the web UI (@domainzero)
• it also seems to work on the LAN side. (issue 35)
• but apparently, not for every body (issue 57) so use the PoC again after adding the rule to make sure the firewall does its job.
• install an open source firmware (for example OpenWRT or Tomato) this is NOT magical, OpenWAG200 is vuln: http://sourceforge.net/projects/openwag200/files/OpenWAG200/1.4/
• kill the backdoor after each reboot (issue 61 & TCP-32764-First-Aid)
• use this alternative firmware: amod (thank you pidocchio and nremond)
• redirect the port traffic in your router firewall to a local unused IP and done ([@osisecurite])

Probable source of the backdoor:

• SerComm https://news.ycombinator.com/item?id=6998258 (nice finding :) )
• Confirmed by a header (socket_header.h) in cisco gpl sources (thank you Andreas Fett!)

Backdoor LISTENING ON THE INTERNET confirmed in :

• Linksys WAG120N (@p_w999)
• Netgear DG834B V5.01.14 (@domainzero)
• Netgear DGN2000 1.1.1, 1.1.11.0, 1.3.10.0, 1.3.11.0, 1.3.12.0 (issue 44)
• Netgear WPNT834 (issue 79)
• OpenWAG200 maybe a little bit TOO open ;) (issue 49)

Backdoor confirmed in:

• Cisco RVS4000 fwv 2.0.3.2 & 1.3.0.5 (issue 57)
• Cisco WAP4410N (issue 11)
• Cisco WRVS4400N
• Cisco WRVS4400N (issue 36)
• Diamond DSL642WLG / SerComm IP806Gx v2 TI (https://news.ycombinator.com/item?id=6998682)
• LevelOne WBR3460B (http://www.securityfocus.com/archive/101/507219/30/0/threaded)
• Linksys RVS4000 Firmware V1.3.3.5 (issue 55)
• Linksys WAG120N (issue 58)
• Linksys WAG160n v1 and v2 (@xxchinasaurxx @saltspork)
• Linksys WAG200G
• Linksys WAG320N (http://zaufanatrzeciastrona.pl/post/smieszna-tylna-furtka-w-ruterach-linksysa-i-prawdopodobnie-netgeara/)
• Linksys WAG54G2 (@_xistence)
• Linksys WAG54GS (@henkka7)
• Linksys WRT350N v2 fw 2.00.19 (issue 39)
• Linksys WRT300N fw 2.00.17 (issue 34)
• Netgear DG834[∅, GB, N, PN, GT] version < 5 (issue 19 & issue 25 & issue 62 & jd & Burn2 Dev)
• Netgear DGN1000 (don't know if there is a difference with the others N150 ones... issue 27)

Backdoor may be present in:

• all SerComm manufactured devices (https://news.ycombinator.com/item?id=6998258)
• Linksys WAG160N (http://zaufanatrzeciastrona.pl/post/smieszna-tylna-furtka-w-ruterach-linksysa-i-prawdopodobnie-netgeara/)
• Netgear DG934 probability: probability: 99.99% (http://codeinsecurity.wordpress.com/category/reverse-engineering/)
• Netgear WG602, WGR614 (v3 doesn't work, maybe others...) (http://zaufanatrzeciastrona.pl/post/smieszna-tylna-furtka-w-ruterach-linksysa-i-prawdopodobnie-netgeara/)

Backdoor is not working in:

• Belkin F5D7230-4 6000 (SerComm manufactured product) (issue 51)
• Belkin F9K1002 v3 (SerComm manufactured product)
• Cisco E2000 fwv 1.0.02 (issue 17)
• Cisco Linksys E4200 V1 fwv 1.0.05 (issue 18)
• Cisco Linksys X2000 (issue 40)
• Cisco EPC3925
• Cisco RV082 v03 fw4.2.2.08 (issue 94)
• Linksys E2500 (@Antoniojojojo)
• Linksys E3000 fwv 1.0.04 (issue 16)
• Linksys E3200 Firmware Version: 1.0.04 (Build 1)
• Linksys E4200 Firmware Version: 2.0.26 (issue 53)
• Linksys RV082 v02 fw2.0.2.01-tm (issue 94)
• Linksys WAG354G V.2 EU (issue 69)
• Linksys WRT100 fwv 1.0.00 (Issue 71)
• Linksys WRT110 fwv 1.0.07 (issue 70)
• Linksys WRT120N fwv 1.0.07 (@viniciuskmax)
• Linksys WRT160Nv2 (issue 43)
• Linksys WRT160Nv3
• Linksys WRT320N (issue 31)
• Linksys WRT54GL(v1.1) Firmware v4.30.16
• Linksys WRT54GS v1.52.8 build 001 (thanks Helmut Tessarek)
• Linksys WRT600N running 1.01.36 build 3 (@shanetheclassic & issue 46)

Some clarifications: I didn't want to waste my time in writing a full report, it's a very simple backdoor that really doesn't deserve more than some crappy slides. Moreover, my English is quite bad.

I had a lot of fun in writing / drawing the slides, all the necessary information is in them. If people don't understand them or find them "too full of meme" then - well - it's too bad for them. :)