CVE-2012-2318 in Pidgin
Summary
by MITRE
msg.c in the MSN protocol plugin in libpurple in Pidgin before 2.10.4 does not properly handle crafted characters, which allows remote servers to cause a denial of service (application crash) by placing these characters in a text/plain message.
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Analysis
by VulDB Data Team • 12/05/2021
The vulnerability identified as CVE-2012-2318 resides within the MSN protocol plugin of Pidgin messaging client version 2.10.4 and earlier. This flaw specifically affects the msg.c component responsible for handling message processing within the MSN protocol implementation. The vulnerability manifests when remote servers send specially crafted character sequences within text/plain messages, leading to application instability and potential system crashes. This represents a classic buffer manipulation and input validation issue that undermines the robustness of the messaging client's protocol handling mechanisms.
The technical implementation of this vulnerability stems from insufficient validation and sanitization of incoming message data within the MSN protocol plugin. When Pidgin receives a message containing malformed or specially crafted characters, the msg.c processing function fails to properly handle these sequences, causing memory corruption or unexpected behavior that ultimately results in application termination. This flaw operates at the protocol parsing layer where incoming data streams are processed without adequate boundary checks or character validation routines. The vulnerability aligns with CWE-129, which addresses insufficient validation of length parameters, and CWE-787, concerning out-of-bounds writes. The attack vector requires only that a remote server send maliciously formatted messages through the MSN protocol, making it particularly dangerous as it can be exploited without requiring user interaction or authentication.
From an operational impact perspective, this vulnerability creates significant risks for users relying on Pidgin for MSN communications. The denial of service condition can be triggered by any remote server participating in the MSN network, potentially disrupting communication channels for affected users. Attackers could exploit this vulnerability to repeatedly crash messaging sessions, effectively preventing legitimate communication or creating persistent disruption in enterprise environments where Pidgin is used for instant messaging. The vulnerability also represents a potential vector for more sophisticated attacks if combined with other exploitation techniques, as the application crash could be leveraged to execute additional malicious payloads or to establish a foothold for further compromise.
The remediation strategy for CVE-2012-2318 focuses on implementing proper input validation and sanitization within the affected MSN protocol plugin. This includes strengthening the msg.c component to properly handle all character sequences within text/plain messages, implementing boundary checks for character handling, and adding robust error recovery mechanisms. System administrators should immediately update to Pidgin version 2.10.4 or later, which contains the necessary patches to address the vulnerability. Organizations should also consider implementing network-level monitoring to detect and block suspicious message patterns that may indicate exploitation attempts. The fix should be validated through thorough testing to ensure that legitimate message processing remains functional while preventing the specific character sequences that trigger the crash condition.
The vulnerability demonstrates how protocol implementation flaws can create significant security risks in messaging applications. It highlights the importance of proper input validation in network protocol handlers and the potential for seemingly benign character sequences to cause application instability. From an ATT&CK framework perspective, this vulnerability maps to the T1499.004 technique related to network denial of service, and represents a classic example of how protocol-level vulnerabilities can be exploited to achieve system compromise. The incident underscores the necessity of comprehensive security testing for protocol implementations and the importance of maintaining up-to-date software to protect against known vulnerabilities. Organizations using Pidgin or similar messaging clients should implement regular patch management procedures and conduct vulnerability assessments to identify and remediate similar issues in their messaging infrastructure.