CVE-2015-1463 in Fedora
Summary
by MITRE
ClamAV before 0.98.6 allows remote attackers to cause a denial of service (crash) via a crafted petite packer file, related to an "incorrect compiler optimization."
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Analysis
by VulDB Data Team • 04/12/2022
The vulnerability identified as CVE-2015-1463 affects ClamAV versions prior to 0.98.6 and represents a significant denial of service weakness that can be exploited remotely by attackers. This flaw specifically manifests when ClamAV encounters a crafted petite packer file, causing the antivirus engine to crash and potentially leading to system unavailability. The vulnerability stems from an incorrect compiler optimization that affects how the software processes certain file formats, creating a condition where legitimate file parsing operations can trigger unexpected behavior in the memory management and execution flow of the application.
The technical root cause of this vulnerability lies in compiler optimization artifacts that introduce memory corruption or invalid memory access patterns when processing malformed petite packer files. Petite packer is a file compression utility that creates executable files with specific header structures and compression algorithms. When ClamAV attempts to scan these specially crafted files, the optimized code path fails to properly validate input data or handle edge cases in the file structure, leading to buffer overflows, null pointer dereferences, or other memory access violations that cause the application to terminate abruptly. This issue demonstrates how aggressive compiler optimizations can introduce subtle bugs that may not be apparent during normal testing but become exploitable under specific conditions.
From an operational perspective, this vulnerability creates a substantial risk for organizations relying on ClamAV for malware detection and prevention. Attackers can remotely trigger service disruption by uploading or transmitting maliciously crafted petite packer files to systems running vulnerable ClamAV versions, potentially causing widespread availability issues across networked environments. The impact extends beyond simple service interruption as it can affect email servers, file servers, and other systems that depend on ClamAV for real-time scanning operations. Organizations may experience cascading failures where the crash of ClamAV processes leads to increased system load, potential data loss, or complete scanning service outages that can compromise overall security posture.
The vulnerability aligns with CWE-122, which describes improper restriction of operations within a limited error handling context, and demonstrates how compiler optimization can create security weaknesses that fall outside typical input validation considerations. From an ATT&CK framework perspective, this vulnerability maps to T1499.004, which covers "Endpoint Denial of Service," and represents a classic example of how software flaws in security tools can be weaponized to undermine system availability. The attack surface is particularly concerning as it requires no authentication or elevated privileges, making it accessible to any remote attacker who can influence the files processed by ClamAV. Organizations should implement immediate mitigations including patching to ClamAV version 0.98.6 or later, implementing network-based restrictions on file types that may trigger the vulnerability, and monitoring for unusual crash patterns in antivirus systems.
Mitigation strategies should include not only updating to the patched ClamAV version but also implementing layered defensive measures such as file type filtering, sandboxing suspicious files, and establishing robust monitoring protocols for antivirus service stability. Security teams should also consider implementing network segmentation to limit the impact of potential exploitation and maintain detailed logging of file scanning operations to detect anomalous behavior. The vulnerability serves as a reminder of the critical importance of thorough testing, particularly for security tools that process untrusted input, and highlights the need for maintaining up-to-date software versions to protect against known weaknesses that could be leveraged by threat actors.