CVE-2003-1109 in IP Phone
Summary
by MITRE
The Session Initiation Protocol (SIP) implementation in multiple Cisco products including IP Phone models 7940 and 7960, IOS versions in the 12.2 train, and Secure PIX 5.2.9 to 6.2.2 allows remote attackers to cause a denial of service and possibly execute arbitrary code via crafted INVITE messages, as demonstrated by the OUSPG PROTOS c07-sip test suite.
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Analysis
by VulDB Data Team • 01/22/2025
The vulnerability described in CVE-2003-1109 represents a critical flaw in the Session Initiation Protocol implementation across multiple Cisco network devices and services. This issue affects Cisco IP Phone models 7940 and 7960 along with various IOS versions in the 12.2 train and Secure PIX firewalls running versions 5.2.9 through 6.2.2. The vulnerability stems from inadequate input validation within the SIP processing mechanisms that handle incoming INVITE requests, creating a pathway for remote attackers to exploit the system through malformed or crafted SIP messages. The specific attack vector involves sending specially crafted INVITE messages that trigger buffer overflows or other memory corruption conditions within the affected Cisco implementations.
The technical nature of this vulnerability aligns with CWE-121, which describes heap-based buffer overflow conditions, and CWE-122, which covers stack-based buffer overflow scenarios. These buffer overflow conditions occur when the SIP parser fails to properly validate the length and content of incoming INVITE messages, allowing attackers to exceed allocated memory boundaries. The exploitation process typically involves sending INVITE messages containing oversized headers or malformed parameters that cause the target system to allocate insufficient memory for processing, leading to memory corruption. The OUSPG PROTOS c07-sip test suite specifically demonstrates how these crafted messages can be structured to trigger the vulnerability effectively.
The operational impact of this vulnerability extends beyond simple denial of service conditions to potentially enabling remote code execution on affected systems. When successfully exploited, attackers can cause the targeted Cisco devices to crash or reboot, resulting in service disruption that can severely impact voice communication infrastructure. The potential for arbitrary code execution represents a more serious threat as it could allow attackers to gain unauthorized control over the affected systems, potentially leading to complete network compromise. This vulnerability particularly affects enterprise voice infrastructure where SIP is used extensively for voice over IP communications, making it a high-value target for attackers seeking to disrupt business operations or establish persistent access points.
Mitigation strategies for this vulnerability require immediate implementation of network segmentation and access controls to limit exposure to untrusted networks. Cisco recommends upgrading to patched versions of IOS and Secure PIX software, with specific attention to versions that contain fixes for the SIP processing vulnerabilities. Network administrators should implement rate limiting and message filtering mechanisms to detect and block suspicious INVITE messages before they reach the vulnerable SIP processing components. The implementation of intrusion detection systems with signature-based detection for known malicious SIP patterns can provide additional protection layers. Organizations should also consider disabling SIP processing on devices where it is not essential and implementing proper network monitoring to detect unusual traffic patterns that might indicate exploitation attempts. This vulnerability demonstrates the importance of maintaining up-to-date security patches and following security best practices for voice communication infrastructure as outlined in the ATT&CK framework's network service providers tactics and techniques.