CVE-2015-1462 in Fedora
Summary
by MITRE
ClamAV before 0.98.6 allows remote attackers to have unspecified impact via a crafted upx packer file, related to a "heap out of bounds condition."
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Analysis
by VulDB Data Team • 04/12/2022
The vulnerability identified as CVE-2015-1462 affects ClamAV versions prior to 0.98.6 and represents a critical heap out of bounds condition that can be exploited through crafted UPX packer files. This flaw exists within the antivirus engine's handling of compressed file formats, specifically those processed by the UPX (Ultimate Packer for eXecutables) compression utility. The issue arises when ClamAV attempts to decompress and analyze maliciously crafted UPX-packed files, leading to memory corruption that can be leveraged by remote attackers to execute arbitrary code or cause denial of service conditions.
The technical root cause of this vulnerability stems from inadequate bounds checking within ClamAV's decompression routines for UPX-packed executables. When processing a specially crafted UPX file, the application fails to properly validate the size and structure of the compressed data, resulting in memory accesses that extend beyond allocated heap buffers. This heap out of bounds condition creates opportunities for memory corruption that can be exploited through various attack vectors including remote code execution, information disclosure, or system instability. The vulnerability is classified under CWE-129 as an insufficient bounds checking issue, specifically manifesting as an out-of-bounds read or write operation that can be triggered by malformed input data.
From an operational impact perspective, this vulnerability poses significant risks to organizations relying on ClamAV for malware detection and prevention. Remote attackers can exploit this weakness by delivering malicious UPX-packed files through various channels including email attachments, web downloads, or file sharing systems. The attack surface expands considerably as UPX is commonly used by malware authors to obfuscate their payloads, making this vulnerability particularly dangerous in environments where email filtering, web proxy scanning, or file upload validation relies on ClamAV. The unspecified impact mentioned in the CVE description suggests that exploitation could lead to multiple outcomes including complete system compromise, data exfiltration, or persistent backdoor installation, depending on the specific execution context and target system configuration.
Security professionals should prioritize immediate remediation of this vulnerability by upgrading ClamAV to version 0.98.6 or later, which includes proper bounds checking and memory validation routines for UPX file processing. Organizations should also implement additional defensive measures such as network segmentation, email filtering rules that block known malicious UPX files, and regular security assessments of their antivirus configurations. The ATT&CK framework categorizes this vulnerability under T1059.007 for execution through command and scripting interpreter and T1566 for initial access through spearphishing attachments, highlighting the multi-layered attack surface this flaw creates. System administrators should also monitor for anomalous behavior in antivirus logs and implement intrusion detection systems that can identify attempts to exploit this specific memory corruption vulnerability. Regular patch management processes should be enhanced to ensure rapid deployment of security updates for antivirus solutions, as this vulnerability demonstrates the critical importance of keeping security tools current with the latest threat mitigations.