SDL_mixer: Stack-based buffer overflow in FetchXLaw (CVE-2026-122329)

SDL_mixer versions 3.1.2 through 3.2.4 contain a stack-based buffer overflow in the FetchXLaw() function located in src/decoder_aiff.c. The vulnerability stems from an incorrect calculation of output offsets when processing A-law or mu-law audio samples within AIFF-C files. Successful exploitation allows an attacker to overwrite approximately 1 KB of adjacent stack memory, which can lead to application crashes or potential arbitrary code execution.

Impact

Successful exploitation may result in an application crash (Denial of Service) or potential arbitrary code execution depending on the memory layout and the presence of exploit mitigation protections within the host application.

Recommendation

1. Inventory all applications utilizing SDL_mixer library versions 3.1.2 through 3.2.4.
2. Prioritize upgrading to the latest patched version of SDL_mixer once available.
3. Implement memory safety protections (e.g., stack canaries, DEP, ASLR) at the build or runtime level for applications that process untrusted AIFF-C audio files.
4. Perform input validation or sandboxing for applications that handle AIFF-C files from external, untrusted sources.