CVE-2025-59734
HighCVSS 8.7Exploitation Probability (EPSS)
Low risk7th percentile - higher than 7% of all known CVEs
Summary
Use-after-free vulnerability in the SANM decoder (animation format) in FFmpeg. With a crafted file using subversion <2, an invalid frame size in a FOBJ chunk causes an early return and stores the raw frame in ctx->stored_frame without setting dimensions. A subsequent FTCH chunk re-decodes the frame, initializes buffers and frees the previous buffer, while the GetByteContext object still references the freed memory, leading to a use-after-free write (allocator metadata corruption).
Risk Assessment
May lead to memory corruption and potential arbitrary code execution or denial of service (crash) when processing a malicious SANM file. The issue can be triggered merely by probing whether a file has the SANM format, increasing risk in automated file processing.
Recommendation
Upgrade FFmpeg to version 8.0 or later. Until patched, avoid processing untrusted SANM files and consider restricting automatic format probing.
Other vulnerabilities in FFmpeg
See all- CVE-2017-15672High
The read_header function in libavcodec/ffv1dec.c in FFmpeg 2.4 and 3.3.4 and possibly earlier allows remote attackers to have unspecified impact via a crafted MP4 file, which triggers an out-of-bounds read.
- CVE-2017-14767High
The sdp_parse_fmtp_config_h264 function in libavformat/rtpdec_h264.c in FFmpeg before version 3.3.4 mishandles empty sprop-parameter-sets values, allowing remote attackers to cause a denial of service (heap buffer overflow) or possibly have unspecified other impact via a crafted sdp file.
- CVE-2017-14225High
The av_color_primaries_name function in libavutil/pixdesc.c in FFmpeg 3.3.3 may return a NULL pointer depending on a value contained in a file, leading to a NULL pointer dereference in the avcodec_string function in libavcodec/utils.c.
- CVE-2012-2805High
Unspecified vulnerability in FFMPEG 0.10 allows remote attackers to cause a denial of service.
- CVE-2017-11719High
The dnxhd_decode_header function in libavcodec/dnxhddec.c in FFmpeg versions 3.0 through 3.3.2 allows remote attackers to cause a denial of service (out-of-array access) or possibly have unspecified other impact via a crafted DNxHD file.
- CVE-2017-11665High
The ff_amf_get_field_value function in libavformat/rtmppkt.c in FFmpeg 3.3.2 allows remote RTMP servers to cause a denial of service via a crafted stream, leading to segmentation violation and application crash.
- CVE-2017-9996High
The cdxl_decode_frame function in libavcodec/cdxl.c in FFmpeg before versions 2.8.12, 3.0.8, 3.1.8, 3.2.5, and 3.3.1 does not exclude the CHUNKY format, allowing remote attackers to cause a denial of service (heap-based buffer overflow and application crash) or possibly have unspecified other impact via a crafted file.
- CVE-2017-9995High
In libavcodec/scpr.c in FFmpeg version 3.3 and earlier, before version 3.3.1, height and width data is not properly validated, allowing remote attackers to cause a denial of service (heap-based buffer overflow and application crash) or possibly have unspecified other impact via a crafted file.
- CVE-2017-9993High
FFmpeg versions before 2.8.12, 3.0.x and 3.1.x before 3.1.9, 3.2.x before 3.2.6, and 3.3.x before 3.3.2 do not properly restrict HTTP Live Streaming filename extensions and demuxer names, allowing attackers to read arbitrary files via crafted playlist data.
- CVE-2017-9992High
A heap-based buffer overflow in the decode_dds1 function in libavcodec/dfa.c in FFmpeg before 2.8.12, 3.0.x before 3.0.8, 3.1.x before 3.1.8, 3.2.x before 3.2.5, and 3.3.x before 3.3.1 allows remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via a crafted file.
Original NVD description (English source)
It is possible to cause an use-after-free write in SANM decoding with a carefully crafted animation using subversion <2. When a STOR chunk is present, a subsequent FOBJ chunk will be saved in ctx->stored_frame. Stored frames can later be referenced by FTCH chunks. For files using subversion < 2, the undecoded frame is stored, and decoded again when the FTCH chunks are parsed. However, in process_frame_obj if the frame has an invalid size, there’s an early return, with a value of 0. This causes the code in decode_frame to still store the raw frame buffer into ctx->stored_frame. Leaving ctx->has_dimensions set to false. A subsequent chunk with type FTCH would call process_ftch and decode that frame obj again, adding to the top/left values and calling process_frame_obj again. Given that we never set ctx->have_dimensions before, this time we set the dimensions, calling init_buffers, which can reallocate the buffer in ctx->stored_frame, freeing the previous one. However, the GetByteContext object gb still holds a reference to the old buffer. Finally, when the code tries to decode the frame, codecs that accept a GetByteContext as a parameter will trigger a use-after-free read when using gb. GetByteContext is only used for reading bytes, so at most one could read invalid data. There are no heap allocations between the free and when the object is accessed. However, upon returning to process_ftch, the code restores the original values for top/left in stored_frame, writing 4 bytes to the freed data at offset 6, potentially corrupting the allocator’s metadata. This issue can be triggered just by probing whether a file has the sanm format. We recommend upgrading to version 8.0 or beyond.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS