CVE-2014-2288 in Asterisk
Summary
by MITRE
The PJSIP channel driver in Asterisk Open Source 12.x before 12.1.1, when qualify_frequency "is enabled on an AOR and the remote SIP server challenges for authentication of the resulting OPTIONS request," allows remote attackers to cause a denial of service (crash) via a PJSIP endpoint that does not have an associated outgoing request.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 05/11/2026
The vulnerability described in CVE-2014-2288 represents a critical denial of service flaw within the PJSIP channel driver of Asterisk Open Source versions 12.x prior to 12.1.1. This issue specifically manifests when the qualify_frequency parameter is enabled on an Address of Record (AOR) and the remote SIP server challenges authentication for the resulting OPTIONS request. The flaw exists in the handling of PJSIP endpoints that lack associated outgoing requests, creating a scenario where remote attackers can exploit this condition to crash the Asterisk application. The vulnerability is particularly dangerous because it can be triggered remotely without requiring authentication or prior access to the system, making it an attractive target for attackers seeking to disrupt VoIP services.
The technical root cause of this vulnerability stems from improper input validation and memory management within the PJSIP channel driver's handling of SIP authentication challenges. When qualify_frequency is enabled, the system periodically sends OPTIONS requests to verify endpoint availability and performs authentication challenges as part of the qualification process. However, the driver fails to properly validate the presence of an associated outgoing request before processing the authentication challenge response. This leads to a null pointer dereference or invalid memory access when the system attempts to process the response from a PJSIP endpoint that does not have a corresponding outgoing request context. The flaw is classified under CWE-476 as a NULL Pointer Dereference, which represents a fundamental weakness in the software's error handling mechanisms.
The operational impact of this vulnerability extends beyond simple service disruption, as it can result in complete system crashes that require manual intervention to restore normal operations. When exploited, the vulnerability causes the Asterisk process to terminate abruptly, leading to loss of all active VoIP connections and service interruptions that can affect business communications. This is particularly concerning in enterprise environments where Asterisk serves as a core communication infrastructure, as the denial of service can cascade into broader operational failures. The vulnerability affects the availability aspect of the CIA triad, specifically targeting the system's ability to maintain continuous service delivery. According to ATT&CK framework, this represents a privilege escalation technique through service interruption, as the attacker can leverage this flaw to gain control over service availability without requiring elevated privileges.
Mitigation strategies for CVE-2014-2288 primarily involve applying the official patch released by the Asterisk development team in version 12.1.1, which addresses the underlying memory management issue in the PJSIP channel driver. Organizations should also implement network-level controls to restrict access to SIP endpoints and monitor for unusual authentication challenge patterns that might indicate exploitation attempts. Additionally, configuring qualify_frequency with appropriate intervals and ensuring proper endpoint validation can reduce the attack surface. System administrators should consider implementing intrusion detection systems to monitor for abnormal behavior patterns that could indicate exploitation attempts, while also maintaining regular backup procedures to ensure rapid recovery in case of successful attacks. The vulnerability underscores the importance of keeping VoIP infrastructure updated and following security best practices for real-time communication systems.