CVE-2025-10256 is a vulnerability identified in FFmpeg version 3.2, specifically within the Firequalizer audio filter component (libavfilter/af_firequalizer.c). The root cause is a missing validation check on the return value of the av_malloc_array() function inside the config_input() function. av_malloc_array() is responsible for allocating memory arrays, and if it fails, it returns NULL. Without verifying this return value, the code proceeds to dereference the NULL pointer, causing the application to crash. An attacker can exploit this by crafting a malicious media file designed to trigger this code path when processed with the Firequalizer filter enabled. The consequence is a denial of service (DoS) due to application crash, impacting availability but not confidentiality or integrity. The vulnerability is remotely exploitable without requiring authentication or user interaction, as simply processing the crafted media file is sufficient. The CVSS v3.1 base score is 5.3 (medium severity), reflecting the ease of exploitation and limited impact scope. No known exploits have been reported in the wild to date. The vulnerability highlights the importance of robust error handling in multimedia processing libraries, which are widely used in various applications including media players, streaming services, and content creation tools.

For European organizations, the primary impact of CVE-2025-10256 is denial of service, which can disrupt media processing workflows, streaming services, or any application relying on FFmpeg 3.2 with the Firequalizer filter enabled. This could lead to service outages, degraded user experience, and potential operational downtime. Organizations in sectors such as media production, broadcasting, online streaming platforms, and content delivery networks are particularly at risk. While the vulnerability does not compromise data confidentiality or integrity, repeated or targeted exploitation could cause significant availability issues, potentially affecting business continuity and reputation. Additionally, denial of service in critical media infrastructure could have cascading effects on dependent services or customers. Given the widespread use of FFmpeg in open-source and commercial products, the impact could be broad if unpatched systems are present in the environment.

To mitigate CVE-2025-10256, organizations should first identify all instances of FFmpeg version 3.2 in their environment, especially those using the Firequalizer filter. Immediate mitigation includes disabling the Firequalizer filter when processing media files from untrusted sources to prevent triggering the vulnerability. Monitoring and filtering incoming media files for suspicious or malformed content can reduce exposure. Organizations should track FFmpeg releases and apply patches or upgrade to a fixed version as soon as it becomes available. If upgrading is not immediately feasible, consider sandboxing or isolating media processing components to contain potential crashes and minimize impact on critical systems. Implementing robust input validation and employing media file scanning tools can further reduce risk. Finally, maintain comprehensive logging and alerting to detect abnormal crashes or service disruptions indicative of exploitation attempts.