OESA-2026-3640

FFmpeg is a complete and free Internet live audio and video broadcasting solution for Linux/Unix. It also includes a digital VCR. It can encode in real time in many formats including MPEG1 audio and video, MPEG4, h263, ac3, asf, avi, real, mjpeg, and flash.

Security Fix(es):

FFmpeg versions 2.7 through 8.1.2 contain an out-of-bounds write vulnerability in the TDSC video decoder that allows remote attackers to cause heap corruption by supplying a crafted AVI file that changes frame dimensions across TDSF frames. The tdscparsetdsf() function fails to unreference the existing reference frame before calling avframegetbuffer(), causing tdscblit() and tdsc_yuv2rgb() to write attacker-controlled pixel data beyond the end of the undersized reference frame buffer, resulting in a process crash and potential code execution.(CVE-2026-65703)

FFmpeg versions 3.4 through 8.1.2 contain an out-of-bounds write vulnerability in the vffloodfill video filter that allows attackers to corrupt heap memory by supplying a dynamically sized video stream with filtergraph reinitialization disabled via -reinitfilter 0. When configinput() allocates the points traversal stack based on initial frame dimensions and a subsequent larger frame is processed, filterframe() performs flood-fill neighbor pushes beyond the original allocation boundary, resulting in heap corruption and process crash with potential for code execution depending on heap layout and process hardening.(CVE-2026-65705)

FFmpeg versions from 0.5 up to, but not including, 9.0 contain a signed integer overflow vulnerability in the DVB subtitle parser in libavcodec/dvbsubparser.c that allows attackers to trigger a heap buffer overflow by supplying a crafted WTV file. The overflow causes the bounds-check guard expression to wrap to INTMIN, bypassing the PARSEBUFSIZE comparison and invoking memcpy() with attacker-controlled data into a heap buffer, resulting in an out-of-bounds heap write and potential memory corruption or code execution.(CVE-2026-70628)

FFmpeg versions from 0.5 up to, but not including, 9.0 contain an uninitialized heap memory disclosure vulnerability in the native TIFF decoder in libavcodec/tiff.c. An attacker who can cause FFmpeg to decode a crafted TIFF file can supply a valid Deflate-compressed strip that terminates successfully after producing fewer bytes than the declared strip requires. The tiffunpackzlib() function allocates a heap buffer sized for the full declared strip but copies all declared rows via memcpy() regardless of how many bytes zlib actually decompressed, causing unwritten bytes that can contain stale data from prior heap allocations to be incorporated into decoded image output and potentially exposing sensitive data in persistent services.(CVE-2026-70631)