Cisco IP Phone Software Arbitrary File Read Vulnerability

Vulnerability

Cisco IP Phone software (IP Conference Phones 7832 and 8832, IP Phone 7800 and 8800 Series, and Wireless IP Phone 8821) contains an arbitrary file read vulnerability in the debug shell [1]. The bug is due to insufficient input validation, allowing a user with local shell access to read any file on the device file system. Affected versions include Cisco SIP IP Phone Software Release 14.0 prior to 14.0(1)SR2 on the 7832, 8832, 7800, and 8800 series, and Release 11.0 prior to 11.0(6)Sr2 on the Wireless IP Phone 8821 [1].

Exploitation

An attacker must have authenticated, local access to the device's debug shell. The attacker exploits the vulnerability by providing crafted input to a debug shell command. The lack of proper input validation allows the attacker to traverse the file system and read arbitrary files [1].

Impact

Successful exploitation enables the attacker to read any file on the device file system, leading to disclosure of sensitive information such as configuration files, credentials, or other data stored on the phone [1].

Mitigation

Fixed releases are available: for IP Conference Phones 7832 and 8832 and IP Phone 7800 and 8800 series, upgrade to Release 14.0(1)SR2 or later; for Wireless IP Phone 8821, upgrade to Release 11.0(6)Sr2 or later [1]. No workarounds are documented in the advisory. Customers should consult Cisco's advisory for the most current information and ensure compatibility before upgrading [1].