FFmpeg versions up to 8.1.2 include a heap out‑of‑bounds write in the native PNG and APNG encoders. By crafting a PNG image with a malicious eXIf chunk that contains multiple IFD entries referencing a large payload, the encoder allocates too small a buffer. When png_write_chunk() expands the output, it writes tens of thousands of bytes beyond the allocated space, corrupting heap memory deterministically. The resulting corruption can cause the process to crash and, if exploitation succeeds, arbitrary code execution on the host.

The affected vendor is FFmpeg. All FFmpeg releases through version 8.1.2 are impacted. The vulnerability was fixed by commit b506faf, so FFmpeg 8.1.3 and newer are not vulnerable.

The CVSS score of 8.7 classifies this as high severity. The EPSS score of less than 1% indicates a very low probability of exploitation in the wild, and the vulnerability is not currently listed in CISA’s KEV catalog. The attack can be carried out remotely by supplying a malicious PNG image to ffmpeg’s encoder; no special privileges are required beyond the execution of ffmpeg on the target system.