One of the alerts issued this month concern flaws in Cisco's Unified IP Phone models, specifically related to the company's Skinny Call Control Protocol (SCCP, or "Skinny") and Session Initiation Protocol (Sip), while the other relates to an SQL Injection attack that could affect Cisco's Unified Communications Manager - formerly CallManager.
According to Cisco, a number of its IP phones contain multiple overflow and denial-of-service vulnerabilities. Certain phones running SCCP and/or Sip firmware are vulnerable (see the list at the Cisco advisory). SCCP- and Sip-based phones contain a buffer overflow vulnerability in the handling of DNS responses. A specially-crafted DNS response may be able to trigger a buffer overflow and execute arbitrary code on a vulnerable phone, says Cisco. The hole is fixed in SCCP firmware version 8.0(8) and Sip firmware version 8.8(0).
There are also three vulnerabilities affecting Cisco's Sip devices: a Sip Multipurpose Internet Mail Extensions (MIME) boundary overflow a Telnet Server overflow, and a Sip Proxy Response overflow.
The company also warned that its Unified Communications Manager is vulnerable to an SQL Injection attack in the parameter key of the admin and user interface pages.
A successful attack could allow an authenticated attacker to access information such as usernames and password hashes that are stored in the database, according to this Cisco advisory. Cisco has released free software updates that address this vulnerability.
In January, Cisco warned that its Cisco Unified Communications Manager contains a heap overflow vulnerability in the Certificate Trust List that could allow a hacker to cause a denial-of-service attack or execute arbitrary code.