CVE-2010-3434 in ClamAV
Summary
by MITRE
Buffer overflow in the find_stream_bounds function in pdf.c in libclamav in ClamAV before 0.96.3 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted PDF document. NOTE: some of these details are obtained from third party information.
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Analysis
by VulDB Data Team • 09/25/2021
The vulnerability CVE-2010-3434 represents a critical buffer overflow flaw within the ClamAV antivirus software ecosystem, specifically affecting the libclamav library version prior to 0.96.3. This issue resides in the find_stream_bounds function located within the pdf.c file, which processes PDF document structures during malware scanning operations. The buffer overflow occurs when ClamAV attempts to parse malformed PDF streams, creating a condition where attacker-controlled data can overwrite adjacent memory locations beyond the allocated buffer boundaries. This vulnerability demonstrates a classic software security weakness that enables remote code execution or denial of service scenarios, making it particularly dangerous in environments where ClamAV processes untrusted PDF files.
The technical exploitation of this vulnerability stems from improper input validation and memory management within the PDF parsing routine. When ClamAV encounters a crafted PDF document containing malformed stream data, the find_stream_bounds function fails to properly bounds-check the data before copying it into fixed-size buffers. This allows attackers to craft malicious PDF files that trigger memory corruption during the scanning process, potentially leading to stack smashing or heap corruption. The vulnerability aligns with CWE-121, which categorizes buffer overflow conditions where insufficient bounds checking permits writing beyond allocated memory regions. The flaw operates at the application layer and can be leveraged by remote attackers without requiring authentication, making it particularly attractive for automated exploitation campaigns.
The operational impact of CVE-2010-3434 extends beyond simple service disruption to encompass potential system compromise and widespread denial of service across multiple platforms. Organizations relying on ClamAV for email filtering, file scanning, or endpoint protection face significant risk when processing untrusted PDF content, as malicious actors can craft documents designed to trigger the buffer overflow condition. This vulnerability affects both the local system and network infrastructure, since the application crash can occur during automated scanning processes or when users open suspicious PDF files. The potential for arbitrary code execution means that successful exploitation could allow attackers to gain full control over affected systems, making this vulnerability particularly dangerous in enterprise environments where ClamAV is deployed as a central security solution.
Mitigation strategies for CVE-2010-3434 require immediate software updates to ClamAV version 0.96.3 or later, which contains the necessary patches to address the buffer overflow condition in the pdf.c file. Organizations should implement comprehensive patch management procedures to ensure all ClamAV installations are updated promptly, as the vulnerability affects multiple operating systems including Windows, Linux, and Unix variants. Additional protective measures include configuring ClamAV to scan PDF files with enhanced strictness, implementing network-level filtering to block suspicious PDF content, and establishing monitoring procedures to detect potential exploitation attempts. Security teams should also consider deploying intrusion detection systems that can identify patterns associated with PDF-based buffer overflow attacks and maintain detailed logging of ClamAV scanning activities to detect anomalous behavior that might indicate exploitation attempts. The vulnerability's classification under ATT&CK technique T1059.007 for command and scripting interpreter indicates that exploitation could involve command execution capabilities, further emphasizing the need for layered defensive measures including network segmentation and privilege separation to limit potential damage from successful exploitation attempts.