CVE-2011-1637: Cisco Unified IP Phones 7900 devices (aka TNP phones) with software before 9.2.1 do not properly verify sig...

Security readout for executives and security teams

This issue affects Cisco Unified IP Phones 7900 Series running software before 9.2.1. The phones did not properly verify software image signatures, which could let a local user install a crafted image and gain higher privileges on the phone. Business urgency is mainly for organizations still operating these legacy devices. Exposure is likely limited to environments with Cisco Unified IP Phones 7900 Series still running software older than 9.2.1. Risk increases where device firmware updates, local access, or provisioning paths are weakly controlled. Prioritize remediation where 7900 Series phones remain deployed in sensitive offices, call centers, or networks with weak physical controls. This is not evidenced as actively exploited, but legacy phone infrastructure can become a durable blind spot if firmware control is poor. Mitigation focus: Identify Cisco Unified IP Phones 7900 Series still in service.; Upgrade affected phones to software 9.2.1 or later per Cisco guidance.; Restrict local and administrative access to phone provisioning paths..

Prepared

Jun 28, 2026, 01:17 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.