CVE-2025-5917 is a vulnerability in the widely used libarchive library, which provides a flexible interface for reading and writing streaming archive formats. The issue stems from an off-by-one miscalculation during the handling of filename prefixes and suffixes, resulting in a 1-byte out-of-bounds write. This overflow can corrupt adjacent memory, potentially leading to application crashes or undefined behavior. While the vulnerability does not directly allow for confidentiality or integrity breaches, the memory corruption could be leveraged as a primitive in more complex exploit chains. The flaw affects libarchive versions prior to 3.8.0 and is present in Red Hat Enterprise Linux 10, among other distributions. Exploitation requires local access with limited privileges and user interaction, such as opening a crafted archive file. The CVSS 3.1 score of 2.8 reflects the low severity due to limited impact and exploitation complexity. No public exploits have been reported yet. The vulnerability highlights the importance of careful boundary checks in memory operations within system libraries. Patch availability is implied but no direct links were provided, so users should monitor vendor advisories for updates.

For European organizations, the primary impact is potential application instability or crashes when processing specially crafted archive files using vulnerable libarchive versions. This could disrupt business operations relying on automated archive handling or backup processes. Although the vulnerability is low severity, it could serve as a stepping stone for privilege escalation or code execution if combined with other vulnerabilities, especially in multi-user or shared environments. Organizations running Red Hat Enterprise Linux 10 or other Linux distributions with libarchive prior to 3.8.0 in critical infrastructure, financial services, or government sectors may face increased risk. The requirement for local access and user interaction limits remote exploitation but insider threats or compromised endpoints could exploit this flaw. Overall, the impact is moderate operational risk with low direct confidentiality or integrity concerns.

European organizations should immediately identify systems running vulnerable libarchive versions, particularly those on Red Hat Enterprise Linux 10. They should apply vendor-supplied patches or upgrade libarchive to version 3.8.0 or later as soon as they become available. Until patches are applied, restrict local user permissions to limit the ability to open untrusted archive files. Implement application whitelisting and endpoint protection to detect anomalous archive processing behavior. Conduct user awareness training to avoid opening suspicious archives. Monitor system logs for crashes or unusual activity related to archive handling. For critical systems, consider isolating archive processing tasks in sandboxed environments to contain potential memory corruption effects. Maintain up-to-date backups to recover from potential disruptions caused by crashes or exploitation attempts.