CVE-2002-1487 in Trillian
Summary
by MITRE
The IRC component of Trillian 0.73 and 0.74 allows remote malicious IRC servers to cause a denial of service (crash) by sending the raw messages (1) 206, (2) 211, (3) 213, (4) 214, (5) 215, (6) 217, (7) 218, (8) 243, (9) 302, (10) 317, (11) 324, (12) 332, (13) 333, (14) 352, and (15) 367.
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Analysis
by VulDB Data Team • 05/11/2025
The vulnerability described in CVE-2002-1487 represents a classic denial of service flaw affecting the IRC protocol implementation within Trillian instant messaging software versions 0.73 and 0.74. This weakness stems from inadequate input validation and message handling within the IRC client component, specifically when processing responses from IRC servers. The vulnerability exploits the software's failure to properly sanitize and validate incoming raw IRC messages, creating a condition where malicious servers can trigger unexpected behavior in the client application. The affected messages correspond to standard IRC protocol replies that are typically generated by servers during normal operation, but when crafted in specific ways, they can cause the client to crash or become unresponsive.
The technical flaw manifests through improper buffer handling and state management when processing these specific IRC reply codes. According to CWE classification, this vulnerability aligns with CWE-121, which addresses stack-based buffer overflow conditions, and CWE-122, concerning heap-based buffer overflow issues. The attack vector involves a remote malicious IRC server sending specially crafted messages that exploit memory corruption vulnerabilities in Trillian's IRC client implementation. When the application attempts to process these messages, it encounters malformed data structures or exceeds allocated memory boundaries, resulting in application termination. The specific message codes 206, 211, 213, 214, 215, 217, 218, 243, 302, 317, 324, 332, 333, 352, and 367 represent standard IRC server replies that are normally handled without issue, but when sent in malformed sequences or with unexpected parameters, they trigger the exploitable conditions.
From an operational impact perspective, this vulnerability creates significant security implications for users of Trillian who may unknowingly connect to compromised IRC servers. The denial of service condition affects the availability of the instant messaging client, rendering it unusable for legitimate communication purposes. Attackers can leverage this vulnerability to disrupt service for individual users or potentially create a larger impact if multiple users are simultaneously targeted. The vulnerability also represents a potential entry point for more sophisticated attacks, as the application crash may be followed by additional exploitations or serve as a distraction for other attack vectors. This type of vulnerability falls under the ATT&CK technique T1499.004, which involves network denial of service attacks, and demonstrates how client-side vulnerabilities can be exploited through network protocols to compromise system availability.
The mitigation strategies for this vulnerability primarily involve immediate software updates and patches from the vendor, as well as defensive configuration measures. Users should implement network segmentation to limit exposure to potentially malicious IRC servers, and administrators should consider implementing network access controls that restrict connections to trusted IRC networks. Additionally, the vulnerability highlights the importance of input validation and proper error handling in protocol implementations, suggesting that developers should adopt defensive programming practices such as bounds checking and proper memory management. The incident also underscores the need for regular security assessments of third-party software components and the implementation of intrusion detection systems that can identify and alert on suspicious IRC protocol activity. Organizations should consider implementing application whitelisting policies that restrict execution of vulnerable software versions until patches are deployed, and maintain up-to-date threat intelligence regarding IRC-based attacks and exploitation techniques.