Vulnerabilities: An unspecified bug can cause an unsafe/undocumented TCP port to open allowing for:
Unauthenticated remote access to all pages of the router administration GUI, bypassing any credential prompts under certain common configurations
Direct access to several critical system files
CVE-ID 2013-5122 CWE-288: Authentication Bypass Using an Alternate Path or Channel CVSS Base Score 10 CVSS Temporal Score 8.1 Exploitability Subscore: 10.0
Affected models and firmware: Linksys SMART Wi-Fi Router N600 - EA2700 Firmware Version: 1.0.14 Linksys SMART Wi-Fi Router N750 Smooth Stream EA3500 Firmware Version: 1.0.30 Linksys Maximun Performance N Router E4200v2 Firmware Version: 2.0.36 Linksys Maximun Performance N Router E4200v2 Firmware Version: 2.0.37 Linksys SMART Wi-Fi N900 Media Stream EA4500 Firmware Version: 2.0.36 Linksys SMART Wi-Fi N900 Media Stream EA4500 Firmware Version: 2.0.37 -Web Server Lighttpd 1.4.28 -Running - Linux 2.6.22
Vulnerability Conditions seen in all variations, though not limited too: - Classic GUI has been enabled/installed - Remote Management - Disabled - UPnP - Enabled - IPv4 SPI Firewall Protection - Disabled
Fixes and workarounds:
*** It is strongly advised to those that have the classic GUI firmware installed to do a full WAN side scan for unusual ports that are open that weren't specifically opened by the end user.
It is recommend to upgrade to firmware 2.1.39 on the E4200v2 and EA4500, though it is uncertain if this resolves the problem in all cases. It is recommend to upgrade to firmware 1.1.39 on the EA2700 and EA3500.though it is uncertain if this resolves the problem in all cases.
Vendor: We have been working with Linksys/Belkin Engineers on this problem, and they are still investigating the root cause. We hope to have additional information on this bug soon.
External Links Misc: http://www.osvdb.org/show/osvdb/94768 http://www.securityfocus.com/archive/1/527027 http://securityvulns.com/news/Linksys/EA/1307.html http://www.scip.ch/en/?vuldb.9326 http://www.mobzine.ro/ionut-balan/2013/07/vulnerabilitate-majora-in-linksys-ea2700-ea3500-e4200-ea4500/
Vendor product links: http://support.linksys.com/en-us/support/routers/EA2700 http://support.linksys.com/en-us/support/routers/EA3500 http://support.linksys.com/en-us/support/routers/E4200 http://support.linksys.com/en-us/support/routers/EA4500
Discovered - 07-01-2013 Updated - 08-15-2013 Research Contact - K Lovett, M Claunch Affiliation - SUSnet