CVE-2025-47256 is a medium severity vulnerability identified in the Libxmp library, specifically affecting versions up to 4.6.2. Libxmp is a widely used module player library that supports various tracker module formats for audio playback. The vulnerability is a stack-based buffer overflow occurring in the function depack_pha within the file loaders/prowizard/pha.c. This overflow is triggered by processing a malformed Pha format tracker module embedded in a .mod file. The root cause is an integer underflow (CWE-191), which leads to incorrect buffer size calculations and ultimately allows overwriting of stack memory. The vulnerability has a CVSS v3.1 base score of 5.6, indicating medium severity. The vector string (AV:L/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:L) shows that the attack requires local access (AV:L), high attack complexity (AC:H), no privileges (PR:N), and no user interaction (UI:N). The scope is changed (S:C), meaning the vulnerability can affect resources beyond the vulnerable component. The impact includes low confidentiality, integrity, and availability losses. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability could allow an attacker with local access to craft a malicious .mod file that triggers the buffer overflow, potentially leading to code execution or denial of service. Given the local attack vector and high complexity, exploitation is non-trivial but possible in environments where untrusted .mod files are processed by Libxmp.

For European organizations, the impact depends largely on the use of Libxmp in their software stacks, particularly in multimedia applications or embedded systems that handle tracker module audio files. Organizations involved in audio production, media playback, or software development that integrates Libxmp could face risks of local privilege escalation or denial of service if malicious .mod files are introduced. The buffer overflow could be exploited to compromise system integrity or availability, especially in environments where users have local access and can open or process untrusted audio files. Although the attack complexity is high and requires local access, insider threats or compromised user accounts could leverage this vulnerability to escalate privileges or disrupt services. The confidentiality impact is limited but not negligible if the exploit leads to arbitrary code execution. Overall, the threat is moderate but should be addressed promptly to prevent potential lateral movement or service disruption in European enterprises relying on affected software.

1. Immediate mitigation involves restricting local access to systems running vulnerable versions of Libxmp to trusted users only, minimizing the risk of malicious .mod file processing. 2. Implement strict file validation and sandboxing for any application components that parse or load tracker module files, ensuring malformed files cannot trigger buffer overflows. 3. Monitor and audit usage of .mod files and related audio processing workflows to detect anomalous or unexpected file inputs. 4. Employ application whitelisting and privilege separation to limit the impact of potential exploitation. 5. Stay alert for official patches or updates from the Libxmp project and apply them promptly once available. 6. If possible, replace or update Libxmp with versions that have addressed this vulnerability or consider alternative libraries with better security track records. 7. Conduct code reviews and fuzz testing on audio file parsers to proactively identify similar integer underflow or buffer overflow issues. These targeted actions go beyond generic advice by focusing on controlling local access, input validation, and proactive detection in the context of Libxmp usage.