CVE-2026-125206
LowCVSS 2.5Summary
FFmpeg through 9.0.2 contains an out-of-bounds read vulnerability in the prores_ks encoder's get_alpha_data() that reads before the blocks buffer for interlaced frames with odd heights. Attackers can supply video with alpha and odd height encoded to interlaced ProRes 4444, causing out-of-bounds memory to be encoded into the output alpha plane.
Risk Assessment
Memory contents may be disclosed in encoded video and process crashes may occur. Affects services transcoding untrusted ProRes 4444 video.
Recommendation
Update FFmpeg to a patched version. Validate or restrict processing of untrusted interlaced ProRes 4444 video files.
Other vulnerabilities in FFmpeg
See all- CVE-2026-125270Medium
FFmpeg through 9.0.2 contains a heap out-of-bounds read vulnerability in v4l2_buffer_swframe_to_buf() in libavcodec/v4l2_buffers.c that mishandles frames with negative linesize. Attackers can supply bottom-up AVI or PNM/PFM files that are transcoded to a V4L2 M2M encoder, crashing the application or leaking heap memory into encoded output.
- CVE-2026-125269High
FFmpeg through 9.0.2 contains a double free vulnerability in libavcodec/cbs_sei.c where cbs_sei_delete_message() leaves a stale extension_data reference that ff_cbs_sei_add_message() reuses. Attackers can supply a crafted H.264 stream with a display orientation SEI message followed by payload extension data, processed by h264_metadata with display_orientation=insert, to corrupt heap memory.
- CVE-2026-125268Low
FFmpeg through 9.0.2 contains an uninitialized memory disclosure vulnerability in the CineForm HD decoder. A crafted CFHD file with an ImageHeight tag exceeding coded band heights can cause uninitialized heap bytes to be filtered into decoded video output.
- CVE-2026-125267High
FFmpeg before 8.1.3 and 9.x before 9.0.2 contains a heap out-of-bounds write vulnerability in the APAC decoder in libavcodec/apac.c caused by an unreset bitstream index. Attackers can supply a crafted APAC file whose growing bitstream_index triggers an integer overflow, bypassing the reallocation check so memcpy() corrupts heap memory or crashes the application.
- CVE-2026-125266Low
FFmpeg through 9.0.2 contains an uninitialized stack memory disclosure vulnerability in old_codec23() of libavcodec/sanm.c. A crafted LucasArts SMUSH/SANM animation using codec 23 with an inline table can expose decoder process stack memory in output video.
- CVE-2026-125265Medium
FFmpeg through 9.0.2 contains a use-after-free vulnerability in libavcodec/nvdec.c because ff_nvdec_start_frame() fails to reset ctx->bitstream after slice errors. Attackers can supply crafted video that abandons a picture before end_frame, causing cuvidDecodePicture() to read freed heap memory, crashing applications or exposing stale heap contents.
- CVE-2026-125264Medium
FFmpeg through 9.0.2 contains an uncontrolled resource consumption vulnerability in parse_frame_header() in libavcodec/jpegxl_parser.c that fails to validate TOC entry counts against remaining input. Attackers can supply a crafted JPEG XL frame header with a permuted TOC and huge toc_count, making the parser loop excessively and exhaust CPU.
- CVE-2026-125263Medium
FFmpeg 9.0 through 9.0.2 built with liblcevc_dec fails to validate LCEVC enhanced output dimensions against max_pixels in libavcodec/decode.c before frame allocation. Attackers can supply crafted H.264, HEVC or VVC streams declaring huge LCEVC resolutions to force oversized get_buffer2() allocations and exhaust memory.
- CVE-2026-125262High
FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in libavcodec/lcevcdec.c because LCEVC output picture dimensions are not validated against the allocated frame. Attackers can embed crafted LCEVC enhancement data with differing global configurations in H.264 or HEVC streams to corrupt heap memory in decoding applications.
- CVE-2026-125261Medium
FFmpeg through 9.0.2 contains an out-of-bounds read vulnerability in the SGI encoder's encode_frame() in libavcodec/sgienc.c, where unsigned size variables mis-handle negative linesize frames. Attackers can supply a video whose display matrix triggers autorotate vflip, so transcoding to SGI images reads pixel data far outside the frame and crashes the process.
Original NVD description (English source)
FFmpeg through 9.0.2 contains an out-of-bounds read vulnerability in the prores_ks encoder's get_alpha_data() that reads before the blocks buffer for interlaced frames with odd heights. Attackers can supply video with alpha and odd height encoded to interlaced ProRes 4444, causing out-of-bounds memory to be encoded into the output alpha plane.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS