CVE-2010-2838 in Unified Communications Manager
Summary
by MITRE
The SendCombinedStatusInfo implementation in Cisco Unified Communications Manager (aka CUCM, formerly CallManager) 7.0SU before 7.0(2a)SU3, 7.1 before 7.1(5), and 8.0 before 8.0(3) allows remote attackers to cause a denial of service (process failure) via a malformed SIP REGISTER message, aka Bug ID CSCtf66305.
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Analysis
by VulDB Data Team • 03/03/2017
The vulnerability described in CVE-2010-2838 represents a critical denial of service flaw within Cisco Unified Communications Manager systems that affects multiple versions of the platform. This issue specifically targets the SendCombinedStatusInfo functionality which is responsible for processing status information within the unified communications environment. The vulnerability manifests when the system receives a malformed SIP REGISTER message that triggers an improper handling of the received data, leading to process failure and subsequent service disruption. The affected versions include Cisco Unified Communications Manager 7.0SU before 7.0(2a)SU3, 7.1 before 7.1(5), and 8.0 before 8.0(3), indicating this weakness persisted across several major releases of the telecommunications platform.
The technical flaw resides in the insufficient input validation and error handling mechanisms within the SendCombinedStatusInfo implementation. When a SIP REGISTER message is received with malformed parameters or unexpected data structures, the system fails to properly sanitize or reject the invalid input before processing it through the status information handling routines. This lack of proper boundary checking and data validation creates an exploitable condition where an attacker can craft a specific SIP REGISTER message that will cause the target process to crash or terminate unexpectedly. The vulnerability operates at the application layer of the network stack, leveraging the Session Initiation Protocol which is fundamental to VoIP communications, making it particularly dangerous in enterprise environments where unified communications systems are critical infrastructure components.
The operational impact of this vulnerability extends beyond simple service disruption to potentially compromise business continuity and communication infrastructure reliability. Organizations relying on Cisco Unified Communications Manager for their voice and video communication services face significant risk when this vulnerability is exploited, as the denial of service can render entire communication systems inoperable. Attackers can leverage this weakness to repeatedly send malformed SIP REGISTER messages, causing sustained service interruptions that may last until the affected processes are manually restarted or the system is rebooted. This vulnerability particularly affects enterprise environments where communication systems are under constant load and where any disruption can impact productivity and customer service operations. The flaw can be exploited remotely without requiring authentication, making it particularly dangerous as it can be triggered from any location with network access to the affected system.
Mitigation strategies for this vulnerability should focus on immediate patch application and network-level protections. Cisco released patches addressing this issue in the specified version updates, and organizations should prioritize deployment of the appropriate software releases to remediate the vulnerability. Network administrators should implement SIP-specific filtering rules and rate limiting mechanisms to prevent malformed SIP messages from reaching the affected systems. The vulnerability aligns with CWE-129, Input Validation, and CWE-20, Improper Input Validation, as it demonstrates insufficient validation of received SIP message parameters. From an ATT&CK framework perspective, this vulnerability maps to T1499.004, Endpoint Denial of Service, and T1595.001, Network Device Denial of Service, as it specifically targets network infrastructure components to achieve service disruption. Additionally, implementing intrusion detection systems that can identify and block suspicious SIP traffic patterns will provide an additional layer of defense against exploitation attempts. Organizations should also conduct regular vulnerability assessments to ensure that all communication infrastructure components remain protected against similar flaws that may emerge in the future.