Cisco Details New VoIP, Router Vulnerabilities

Cisco Wednesday revealed a pair of vulnerabilities, one in its Unified CallManager 5.0 software, the other in the Web-based interface used to configure Cisco routers.

Unified CallManager 5.0, software that handles call processing for Cisco VoIP solutions, has two flaws in its command line management interface (CLI) that could allow a logged-in administrator to gain root access privileges and execute code, overwrite files, and launch denial of service attacks, Cisco said.

The Unified CallManager 5.0 software, which Cisco upgraded in March to add support for session initiation protocol (SIP), also includes a buffer overflow vulnerability that attackers can exploit by placing excessively long hostnames into SIP requests along with malicious code, paving the way for code execution and denial of service attacks.

In an advisory, Cisco's Product Security Incident Response Team (PSIRT) said that free software will be made available to address the vulnerabilities.

Symantec, in a bulletin to subscribers of its DeepSight Threat Management System, said the two CLI flaws do not require an exploit and rated the overall severity of the CallManager issues as 10 on a scale of 10.Ethan Simmons, a partner at Boston-based solution provider NetTeks, said that for a CallManager solution to be compromised by one of these attacks, it would to have been put together very poorly. "No one in their right mind would implement an IP voice solution that was exposed directly to the Internet, or for that matter, even internal users," Simmons said.

To prevent unauthorized access, CallManager 5.0 solutions should be implemented using VLANs and access control lists that limit access to the actual call processing servers, Simmons added.

Cisco also revealed a vulnerability that affects the Cisco Router Web Setup tool (CRWS), used to configure routers. This flaw hinges on the application's failure to properly authenticate remote Web-based users, and could allow an attacker to gain elevated administration privileges.

Symantec rated the severity of this threat 10 out of 10 and in a DeepSight bulletin said it's likely this flaw could be leveraged by miscreants to launch additional attacks.

Cisco released software fixes that address the issue, which affects CRWS for Cisco SOHO and Cisco 800 series routers with version prior to 3.3.0 build 31.0