CVE-2008-1332 in Asterisk
Summary
by MITRE
Unspecified vulnerability in Asterisk Open Source 1.2.x before 1.2.27, 1.4.x before 1.4.18.1 and 1.4.19-rc3; Business Edition A.x.x, B.x.x before B.2.5.1, and C.x.x before C.1.6.2; AsteriskNOW 1.0.x before 1.0.2; Appliance Developer Kit before 1.4 revision 109393; and s800i 1.0.x before 1.1.0.2; allows remote attackers to access the SIP channel driver via a crafted From header.
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Analysis
by VulDB Data Team • 12/24/2017
The vulnerability described in CVE-2008-1332 represents a critical security flaw affecting multiple versions of the Asterisk open source telephony platform and its commercial variants. This issue resides within the SIP channel driver implementation, which serves as the core component responsible for handling Session Initiation Protocol communications in Asterisk systems. The vulnerability manifests when the system processes a specially crafted From header in SIP messages, creating an opportunity for remote attackers to gain unauthorized access to the telephony infrastructure. The affected versions span across several major release lines including 1.2.x, 1.4.x, and various commercial editions, indicating this was a widespread issue impacting the foundational telephony software used by organizations worldwide for voice communication services.
The technical nature of this vulnerability stems from insufficient validation and sanitization of the From header field in SIP signaling messages. When Asterisk processes incoming SIP requests, it fails to properly validate the From header content, allowing malicious actors to inject crafted data that can bypass normal access controls and authentication mechanisms. This flaw operates at the protocol level within the SIP channel driver, which is responsible for managing SIP trunking and peer-to-peer communications. The vulnerability enables attackers to potentially establish unauthorized SIP sessions, access internal telephony resources, and potentially escalate privileges within the system. According to CWE classification, this represents a weakness in input validation that could lead to information disclosure, privilege escalation, or unauthorized access to telephony services. The attack vector is particularly concerning as it requires only network-level access to exploit, making it highly accessible to remote threat actors.
The operational impact of this vulnerability extends far beyond simple information disclosure, potentially compromising entire telephony infrastructures used by businesses, telecommunications providers, and government organizations. Organizations running affected Asterisk versions face risks including unauthorized phone calls, toll fraud, eavesdropping on voice communications, and potential system compromise through lateral movement. The vulnerability affects not only traditional PBX deployments but also unified communications systems that rely on Asterisk for voice routing and management. Given that many organizations use Asterisk as their primary telephony platform, the potential for widespread disruption is significant. The attack could result in substantial financial losses through fraudulent calling, regulatory compliance violations, and service interruptions that affect business continuity. According to ATT&CK framework, this vulnerability maps to techniques involving credential access and privilege escalation through protocol manipulation, making it a critical threat to enterprise communication systems.
Mitigation strategies for CVE-2008-1332 primarily focus on immediate software updates and patches provided by Digium to address the specific validation issues in the SIP channel driver. Organizations should prioritize upgrading to patched versions of Asterisk, including the 1.2.27, 1.4.18.1, and 1.4.19-rc3 releases, along with corresponding commercial editions. Network-level defenses should include implementing SIP-specific firewalls, rate limiting for SIP traffic, and monitoring for suspicious From header patterns. Additional protective measures involve configuring proper access controls, implementing strong authentication mechanisms, and conducting regular security audits of telephony systems. Organizations should also consider deploying intrusion detection systems specifically tuned to detect SIP-based attacks and establish network segmentation to limit the potential impact of successful exploitation. The vulnerability highlights the importance of maintaining current security patches for telephony infrastructure and demonstrates how protocol-level flaws can create cascading security issues in communication systems that form the backbone of modern enterprise networks.