CVE-2015-8924 in libarchive
Summary
by MITRE
The archive_read_format_tar_read_header function in archive_read_support_format_tar.c in libarchive before 3.2.0 allows remote attackers to cause a denial of service (out-of-bounds read) via a crafted tar file.
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Analysis
by VulDB Data Team • 09/19/2022
The vulnerability identified as CVE-2015-8924 represents a critical out-of-bounds read flaw within the libarchive library's tar format processing functionality. This issue specifically affects the archive_read_format_tar_read_header function located in the archive_read_support_format_tar.c source file, which is part of the broader libarchive software suite used extensively across various operating systems and applications for handling archive files. The vulnerability arises from insufficient input validation and boundary checking when processing specially crafted tar archive files, creating a scenario where maliciously constructed archive data can trigger memory access violations.
The technical implementation of this vulnerability stems from the function's failure to properly validate the size and structure of tar headers before attempting to read data from memory locations. When a malformed tar file is processed, the function performs memory reads beyond the allocated buffer boundaries, leading to unpredictable behavior and potential system instability. This type of flaw falls under the CWE-125 vulnerability category, which specifically addresses out-of-bounds read conditions that can result in information disclosure, application crashes, or potentially more severe consequences depending on the execution context. The vulnerability is particularly concerning because it can be exploited remotely through network-based attacks or via malicious file attachments, making it a significant threat to systems that process untrusted archive data.
The operational impact of this vulnerability extends beyond simple denial of service conditions, as it can potentially be leveraged for more sophisticated attacks within the ATT&CK framework's privilege escalation and persistence categories. Systems that automatically process or decompress tar files from untrusted sources become vulnerable to exploitation, including web servers handling file uploads, backup systems processing archived data, and any application that relies on libarchive for archive handling. The out-of-bounds read condition can cause applications to crash or behave unpredictably, creating opportunities for attackers to either disrupt services through persistent denial of service attacks or potentially extract sensitive information from memory through information disclosure attacks. The vulnerability affects a wide range of systems since libarchive is a widely-used library that serves as the foundation for many archive handling utilities and applications across different platforms.
Mitigation strategies for CVE-2015-8924 require immediate patching of affected systems with libarchive version 3.2.0 or later, which includes the necessary boundary checks and input validation fixes. Organizations should also implement defensive measures such as restricting access to archive processing capabilities for untrusted users, validating file types before processing, and implementing sandboxing techniques for archive handling operations. Network-based mitigations include configuring firewalls to restrict access to services that process archive files and implementing content filtering systems to detect and block suspicious archive file attachments. The vulnerability demonstrates the critical importance of proper input validation and boundary checking in security-critical libraries, as highlighted by the ATT&CK framework's emphasis on preventing memory corruption vulnerabilities that can lead to privilege escalation. Regular security assessments and vulnerability scanning should be conducted to identify systems running older versions of libarchive, and automated patch management systems should be implemented to ensure timely remediation of similar vulnerabilities.