CVE-2013-6497 in ClamAV
Summary
by MITRE
clamscan in ClamAV before 0.98.5, when using -a option, allows remote attackers to cause a denial of service (crash) as demonstrated by the jwplayer.js file.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 02/25/2022
The vulnerability identified as CVE-2013-6497 affects ClamAV's clamscan utility version 0.98.4 and earlier, specifically when the -a option is employed during file scanning operations. This issue represents a denial of service condition that can be exploited remotely by attackers who craft malicious input files designed to trigger crashes in the scanning process. The vulnerability was demonstrated using the jwplayer.js file, indicating that web-based JavaScript files can serve as effective attack vectors for this particular flaw. The affected version of ClamAV represents a critical security gap in malware detection systems, as it allows adversaries to disrupt legitimate scanning operations without requiring elevated privileges or direct system access.
The technical root cause of this vulnerability stems from inadequate input validation and memory handling within the clamscan utility when processing certain file formats. When the -a option is activated, ClamAV attempts to scan files with additional aggressive detection methods that may not properly handle malformed or specially crafted input. The jwplayer.js file demonstrates how JavaScript code can be structured to exploit buffer overflow conditions or memory corruption scenarios that cause the scanning process to terminate unexpectedly. This flaw operates at the application layer and specifically targets the file parsing mechanisms that ClamAV employs during its scanning routines, making it particularly dangerous in environments where automated scanning is critical for security operations.
The operational impact of CVE-2013-6497 extends beyond simple service disruption to potentially compromise entire security infrastructure. Organizations relying on ClamAV for email filtering, file upload validation, or endpoint protection may experience complete system outages when attackers exploit this vulnerability through malicious file uploads or network-based attacks. The remote exploitation capability means that attackers do not need physical access to systems or knowledge of internal network structures to trigger the denial of service condition. This vulnerability aligns with attack patterns documented in the MITRE ATT&CK framework under the T1499 category for network denial of service, while also potentially supporting lateral movement strategies when primary defenses are compromised. The impact is particularly severe in enterprise environments where ClamAV serves as a central security control for content filtering and malware detection.
Mitigation strategies for CVE-2013-6497 primarily focus on immediate version upgrades to ClamAV 0.98.5 or later, which contain patches addressing the specific memory handling issues that cause the crashes. Organizations should also implement network segmentation and file validation controls to prevent potentially malicious files from reaching scanning systems. The use of alternative scanning parameters or disabling the -a option where possible can provide temporary workarounds while permanent fixes are deployed. Security teams should monitor for exploitation attempts through network traffic analysis and implement intrusion detection systems that can identify patterns associated with this specific vulnerability. Additionally, regular security assessments should verify that ClamAV installations are properly updated and that scanning configurations do not inadvertently enable vulnerable processing modes. This vulnerability highlights the importance of maintaining up-to-date security tooling and implementing comprehensive patch management processes to prevent exploitation of known weaknesses in security infrastructure components.