CVE-2010-2837 in Unified Communications Manager
Summary
by MITRE
The SIPStationInit implementation in Cisco Unified Communications Manager (aka CUCM, formerly CallManager) 6.1SU before 6.1(5)SU1, 7.0SU before 7.0(2a)SU3, 7.1SU before 7.1(3b)SU2, 7.1 before 7.1(5), and 8.0 before 8.0(1) allows remote attackers to cause a denial of service (process failure) via a malformed SIP message, aka Bug ID CSCtd17310.
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Analysis
by VulDB Data Team • 03/03/2017
The vulnerability identified as CVE-2010-2837 represents a critical denial of service flaw within Cisco Unified Communications Manager's SIPStationInit component, affecting multiple versions of the enterprise communication platform. This issue specifically targets the processing of Session Initiation Protocol messages, which form the backbone of VoIP communication systems. The vulnerability stems from inadequate input validation mechanisms within the SIP message handling routine, allowing malicious actors to craft specially formatted SIP messages that trigger unexpected behavior in the affected Cisco CUCM versions. The flaw operates at the protocol level, making it particularly dangerous as it can be exploited without requiring authentication or prior access to the system. According to the Cisco bug ID CSCtd17310, this vulnerability manifests when the system encounters malformed SIP messages that exceed expected parameter boundaries or contain unexpected data structures in the SIP headers or body.
The technical exploitation of this vulnerability occurs through the manipulation of SIP message parameters that are processed by the SIPStationInit module. When the affected Cisco CUCM system receives a malformed SIP message containing crafted payload data, the parsing routine fails to properly handle the unexpected input, leading to process termination or system instability. This behavior aligns with CWE-129, which describes improper validation of input boundaries, and CWE-707, which covers improper use of potentially dangerous API calls. The vulnerability specifically affects the SIP signaling processing pipeline where the system attempts to initialize SIP station components, causing the application to crash or become unresponsive. The malformed SIP messages typically contain oversized fields, invalid encoding sequences, or unexpected parameter combinations that overwhelm the input validation logic in the SIP message parser, resulting in memory corruption or resource exhaustion conditions that ultimately lead to process failure.
The operational impact of this vulnerability extends beyond simple service disruption, potentially compromising the entire communication infrastructure of organizations relying on Cisco Unified Communications Manager. In enterprise environments where CUCM serves as the primary communication platform, a successful exploitation could result in complete loss of VoIP functionality, affecting thousands of users and critical business operations. The vulnerability's remote nature means that attackers can exploit it from outside the network perimeter, making it particularly dangerous for organizations with limited network segmentation. The potential for cascading failures exists when the SIPStationInit component failure affects downstream services or when multiple simultaneous attacks occur, potentially leading to extended outages that can last from minutes to hours depending on system recovery mechanisms. Organizations using affected versions of CUCM may experience disruption to emergency communication systems, business continuity services, and critical telephony infrastructure that depends on the platform's SIP handling capabilities.
Mitigation strategies for CVE-2010-2837 focus primarily on applying official Cisco security patches and updates to bring affected systems up to supported versions. The recommended approach involves upgrading to the patched versions specified in Cisco's advisory, which include 6.1(5)SU1, 7.0(2a)SU3, 7.1(3b)SU2, 7.1(5), and 8.0(1) respectively. Network administrators should implement additional protective measures such as SIP message filtering at perimeter firewalls, rate limiting for SIP traffic, and monitoring for suspicious SIP message patterns that could indicate exploitation attempts. The implementation of proper input validation controls and the deployment of intrusion detection systems capable of identifying malformed SIP traffic can provide additional layers of defense. Organizations should also consider implementing network segmentation strategies to limit the potential impact of successful attacks and establish incident response procedures specifically tailored to handle SIP-based denial of service attacks. According to ATT&CK framework, this vulnerability maps to T1499.004 which covers network denial of service attacks, and T1071.004 which covers application layer protocol usage, making it a significant concern for enterprise security teams managing unified communications infrastructure.