CVE-2025-5916 is an integer overflow vulnerability identified in the libarchive library, specifically triggered when processing Web Archive (WARC) files that claim to contain more than INT64_MAX - 4 content bytes. The flaw arises because the library does not properly handle extremely large content length values, leading to an integer overflow or wraparound during internal calculations. This can cause unpredictable program behavior such as memory corruption or denial-of-service conditions when applications attempt to process these crafted WARC archives. The vulnerability affects libarchive versions prior to 3.8.0 and has been reported in Red Hat Enterprise Linux 10. Exploitation requires local access with low privileges and user interaction, such as opening or processing a malicious WARC file. The CVSS v3.1 base score is 3.9, reflecting low severity due to limited impact on confidentiality and integrity, and the requirement for user interaction and privileges. No known exploits are currently reported in the wild. The vulnerability is significant for applications that rely on libarchive for handling WARC files, commonly used in web archiving and digital preservation contexts. Without proper validation, attackers could craft WARC files that trigger the overflow, potentially causing application crashes or memory corruption, which might be leveraged for further attacks depending on the application context.

For European organizations, the primary impact of CVE-2025-5916 lies in potential denial-of-service conditions or application instability when processing malicious WARC files. Organizations involved in web archiving, digital libraries, or data preservation that utilize libarchive for WARC processing are at risk. While the vulnerability does not directly compromise confidentiality or integrity, memory corruption could theoretically be exploited in complex attack chains. The requirement for local access and user interaction limits remote exploitation, reducing the risk for many enterprise environments. However, organizations that allow users to upload or process untrusted WARC files could face service disruptions or application crashes. This could impact availability of critical archival systems or services. Additionally, organizations relying on Red Hat Enterprise Linux 10 or similar distributions with vulnerable libarchive versions should be aware of this risk. The low CVSS score indicates limited severity, but the potential for denial-of-service and stability issues warrants timely patching and mitigation in sensitive environments.

1. Upgrade libarchive to version 3.8.0 or later where the integer overflow issue is fixed. 2. Apply all relevant security updates provided by Red Hat for Red Hat Enterprise Linux 10 as soon as they become available. 3. Implement strict input validation and sanitization for WARC files before processing, especially if files originate from untrusted sources. 4. Restrict user permissions to limit who can process or upload WARC files, minimizing exposure to malicious archives. 5. Employ application-level sandboxing or containerization for processes handling WARC files to contain potential crashes or memory corruption. 6. Monitor application logs and system behavior for signs of crashes or abnormal processing related to WARC files. 7. Educate users about the risks of opening untrusted archive files and enforce policies to prevent inadvertent processing of malicious content. 8. Consider disabling WARC file processing in libarchive if not required by the organization’s workflows.