CVE-2002-1362 in mICQ
Summary
by MITRE
mICQ 0.4.9 and earlier allows remote attackers to cause a denial of service (crash) via malformed ICQ message types without a 0xFE separator character.
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Analysis
by VulDB Data Team • 05/29/2019
The vulnerability identified as CVE-2002-1362 affects mICQ version 0.4.9 and earlier implementations, representing a classic denial of service weakness in instant messaging protocols. This issue stems from insufficient input validation within the message parsing mechanism of the mICQ client software, which is designed to interface with the ICQ messaging network. The flaw specifically manifests when the software encounters malformed ICQ message types that lack the required 0xFE separator character, a critical delimiter used in the ICQ protocol specification for proper message structure interpretation.
The technical root cause of this vulnerability lies in the protocol parsing logic that fails to properly handle message fragments lacking the expected termination sequence. When mICQ processes incoming messages without the 0xFE separator, the application's message parsing routine becomes confused and attempts to interpret incomplete or malformed data structures. This parsing failure results in memory corruption or stack overflow conditions that ultimately lead to application termination and system crash. The vulnerability operates at the application layer of the network stack, making it particularly dangerous as it can be exploited through network-based attacks without requiring local system access or authentication.
From an operational impact perspective, this vulnerability creates significant disruption potential for users relying on mICQ as their primary communication tool. Attackers can remotely trigger service degradation by sending specially crafted malformed messages that cause the client application to crash repeatedly. This type of denial of service attack effectively renders the targeted client unusable until manual intervention occurs, requiring users to restart their applications and potentially lose ongoing conversations. The impact extends beyond individual users to potentially affect larger communication networks where multiple users rely on the same messaging infrastructure, creating cascading failures in communication services.
The vulnerability aligns with CWE-129, which addresses improper validation of input boundaries, and demonstrates characteristics consistent with ATT&CK technique T1499.004, which covers network disruption through service availability attacks. Security professionals should note that this flaw represents an early example of protocol-based denial of service vulnerabilities that were common in instant messaging clients of that era. The lack of proper input sanitization and boundary checking in the mICQ implementation creates an attack surface that can be exploited by any remote attacker with network access to the target system.
Mitigation strategies for this vulnerability should include immediate software updates to versions that properly validate message structures and implement robust input sanitization routines. System administrators should consider implementing network-level filtering to detect and block malformed ICQ messages before they reach vulnerable client applications. Additionally, users should be educated about the risks of accepting messages from untrusted sources and should regularly update their messaging client software to address known vulnerabilities. The implementation of proper error handling and graceful degradation mechanisms within the application can also help prevent complete crashes when malformed data is encountered, providing users with more resilient communication services.