CVE-2012-3845 in LAN Messenger
Summary
by MITRE
Buffer overflow in LAN Messenger 1.2.28 and earlier allows remote attackers to cause a denial of service (crash) via a long string in an initiation request.
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Analysis
by VulDB Data Team • 07/05/2025
The vulnerability identified as CVE-2012-3845 represents a critical buffer overflow flaw within LAN Messenger version 1.2.28 and earlier installations. This issue manifests when the application processes initiation requests containing excessively long strings, creating a condition where memory boundaries are exceeded during data handling operations. The flaw resides in the protocol implementation that governs how client connections are established within the local area network messaging system, making it particularly dangerous in enterprise environments where such messaging tools are widely deployed.
From a technical perspective, the buffer overflow occurs during the parsing of incoming connection initiation messages where the application fails to properly validate the length of string data before copying it into fixed-size memory buffers. This classic programming error allows malicious actors to craft specially crafted packets containing oversized strings that exceed the allocated buffer space, resulting in memory corruption that ultimately leads to application termination. The vulnerability falls under the CWE-121 category of stack-based buffer overflow, though it may also exhibit characteristics of heap-based overflow depending on the specific implementation details of the string handling routines.
The operational impact of this vulnerability extends beyond simple denial of service conditions, as it can be exploited to cause complete application crashes across multiple connected systems within the LAN environment. In enterprise settings where LAN Messenger serves as a primary communication tool for internal messaging, this vulnerability could result in significant productivity losses and potential security implications. Attackers could repeatedly exploit this flaw to maintain persistent disruption of communication services, effectively creating a persistent denial of service condition that would require manual intervention to resolve. The remote nature of the attack means that adversaries need not be physically present within the network to exploit this weakness.
Mitigation strategies for CVE-2012-3845 should prioritize immediate patching of affected systems, as the vendor has released updates addressing this specific vulnerability. Organizations should implement network segmentation to limit exposure of vulnerable systems and consider deploying intrusion detection systems that can identify malformed initiation requests. Additionally, input validation mechanisms should be strengthened at multiple layers including network firewalls, application-level filters, and host-based security solutions. The remediation process should also include comprehensive testing to ensure that patched versions properly handle edge cases and that no other similar vulnerabilities exist within the application codebase. This vulnerability highlights the importance of proper memory management practices and input validation in networked applications, aligning with ATT&CK technique T1499.004 for network denial of service attacks and emphasizing the need for secure coding practices as outlined in CWE categories related to buffer overflows and memory corruption vulnerabilities.