CVE-2026-125257

FFmpeg through 9.0.2 Heap Overflow via Nellymoser Encoder Trellis Search

FFmpeg through 9.0.2 contains an off-by-one heap overflow vulnerability in get_exponent_dynamic() in libavcodec/nellymoserenc.c that allows writing one element past the opt and path allocations. Attackers can supply crafted audio to applications encoding Nellymoser with trellis enabled, causing idx to equal OPT_SIZE and overwrite adjacent heap memory.

CVSS 4.0 · 7.3 High EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125253

FFmpeg through 9.0.2 VP9 CBS Superframe Integer Overflow Out-of-Bounds Read

FFmpeg through 9.0.2 contains an integer overflow in cbs_vp9_split_fragment() in libavcodec/cbs_vp9.c that wraps the superframe size check on 32-bit builds. Attackers can supply a crafted VP9 packet with a forged superframe index containing near-2^32 frame sizes, causing out-of-bounds reads that crash 32-bit applications.

CVSS 4.0 · 5.8 Medium EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125250

FFmpeg through 9.0.2 GIF Encoder Heap Buffer Overflow via shrunk_buf Remap

FFmpeg through 9.0.2 contains a heap buffer overflow in the GIF encoder's gif_image_write_image() in libavcodec/gif.c because shrunk_buf is sized from the first frame's linesize. Attackers can supply PAL8 video whose frame linesize grows mid-stream, causing remap_frame_to_palette() to write past shrunk_buf and corrupt the heap during GIF transcoding.

CVSS 4.0 · 8.5 High EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125249

FFmpeg 7.1 through 9.0.2 Heap Out-of-Bounds Write via Vulkan Slice Buffer Sizing

FFmpeg 7.1 through 9.0.2 contains an integer overflow in ff_vk_decode_add_slice() in libavcodec/vulkan_decode.c that miscalculates the Vulkan hwaccel bitstream buffer size. Attackers can supply a crafted stream with over 2 GiB of slice data per frame, causing memcpy() to write past a smaller pooled host-mapped buffer.

CVSS 4.0 · 7.3 High EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125241

FFmpeg through 9.0.2 Heap Buffer Overflow via FLIC Decoder check_pixel_ptr

FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in libavcodec/flicvideo.c that allows attackers to write out of bounds because check_pixel_ptr() checks only one bound with negative-stride frames. Attackers can supply a crafted FLIC file whose RLE and delta chunks write pixel data past frame storage, corrupting heap memory to crash applications or possibly execute code.

CVSS 4.0 · 7.3 High EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125233

FFmpeg through 9.0.2 Heap Buffer Overflow via DVB Subtitle Encoder

FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in dvbsub_encode() in libavcodec/dvbsubenc.c that undercounts each CLUT segment header by two bytes. Attackers can supply a file with many bitmap subtitle rectangles that, when transcoded to the dvbsub encoder, writes past the output buffer and corrupts heap memory.

CVSS 4.0 · 8.5 High EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125229

FFmpeg through 9.0.2 Out-of-Bounds Memory Access in Huffyuv/FFVHUFF Median Predictor

FFmpeg through 9.0.2 contains an out-of-bounds memory access vulnerability in the encode_frame() function of libavcodec/huffyuvenc.c, because encode_init() never validates minimum frame dimensions for the median predictor. Attackers can supply a tiny video, such as a 2-pixel-wide or 1-2-pixel-tall frame, that causes negative sub_median_pred lengths and out-of-bounds reads and writes when transcoded to huffyuv or ffvhuff, crashing the encoder.

CVSS 4.0 · 8.5 High EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125222

FFmpeg through 9.0.2 Heap Buffer Overflow via hap_parse_frame_header()

FFmpeg through 9.0.2 contains an integer overflow vulnerability in hap_parse_frame_header() in libavcodec/hapdec.c that allows attackers to trigger a heap buffer overflow on 32-bit builds. Attackers can craft Hap video frames with Snappy length prefixes that wrap tex_size, causing decompress_chunks_thread() to write outside tex_buf and crash the application or potentially execute code.

CVSS 4.0 · 7.3 High EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125218

FFmpeg through 9.0.2 APNG Encoder Heap Buffer Overflow via encode_apng()

FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in the APNG encoder's encode_apng() function in libavcodec/pngenc.c when frame size changes mid-stream. Attackers can supply crafted media whose resolution grows mid-stream, causing APNG_DISPOSE_OP_BACKGROUND memset writes past prev_frame and crashing or corrupting heap memory in transcoding applications.

CVSS 4.0 · 7.3 High EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125217

FFmpeg through 9.0.2 RoQ DPCM Encoder Uninitialized Heap Memory Disclosure

FFmpeg through 9.0.2 contains an uninitialized memory use vulnerability in roq_dpcm_encode_frame() in libavcodec/roqaudioenc.c that encodes stale heap contents when flushed early. Attackers can supply short audio streams under eight frames for RoQ DPCM transcoding, causing DPCM-quantized uninitialized heap data from frame_buffer to leak into output packets.

CVSS 4.0 · 4.8 Medium EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125214

FFmpeg through 9.0.2 Heap Buffer Overflow in Blu-ray PCM Decoder

FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in pcm_bluray_decode_frame() in libavcodec/pcm-bluray.c on big-endian hosts. Attackers can supply a crafted Blu-ray (M2TS) LPCM stream whose payload length is not a multiple of the sample size, writing attacker-controlled bytes past the audio frame buffer.

CVSS 4.0 · 7.3 High EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125213

FFmpeg through 9.0.2 Heap Buffer Overflow via PSD Decoder RLE Path

FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in the PSD decoder in libavcodec/psd.c that allows attackers to corrupt heap memory on 32-bit builds by supplying a crafted PSD image. Attackers can choose dimensions and channel counts whose product exceeds 4 GB, truncating the av_malloc allocation size so decode_rle() writes attacker-controlled data past the buffer, causing crashes or possible code execution.

CVSS 4.0 · 7.3 High EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125210

FFmpeg through 9.0.2 Heap Overflow in libaribcaption Text Subtitle Decoding

FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in aribcaption_trans_text_subtitle() in libavcodec/libaribcaption.c when decoding with sub_type text. Attackers can supply a crafted ARIB STD-B24 caption stream with zero regions, causing a pointer write past a zero-sized sub->rects allocation and corrupting heap memory.

CVSS 4.0 · 7.3 High EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125209

FFmpeg before 8.1.3 and 9.x before 9.0.2 Heap Buffer Overflow via dvdsubenc.c

FFmpeg before 8.1.3 and 9.x before 9.0.2 contains a heap buffer overflow vulnerability in the DVD subtitle encoder that underestimates RLE output size for odd-width rectangles. Attackers can supply files with crafted bitmap subtitles that, when transcoded to the dvdsub encoder, write past the output buffer and corrupt heap memory.

CVSS 4.0 · 8.5 High EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125206

FFmpeg through 9.0.2 Out-of-Bounds Read via prores_ks Interlaced Alpha Encoding

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.

CVSS 4.0 · 2 Low EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125202

FFmpeg through 9.0.2 Heap Buffer Overflow via HEVC VAAPI Tile Arrays

FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in vaapi_hevc_start_frame() in libavcodec/vaapi_hevc.c that copies unbounded PPS tile counts into fixed-size arrays. Attackers can supply a crafted HEVC bitstream with a large picture and many tiles to write controlled 16-bit values past heap-allocated hwaccel data, corrupting memory in applications decoding with VAAPI.

CVSS 4.0 · 7.3 High EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125201

FFmpeg 7.0 before 8.1.3 and 9.x before 9.0.2 Heap Overflow via vulkan_av1.c

FFmpeg 7.0 before 8.1.3 and 9.x before 9.0.2 contains a heap out-of-bounds write vulnerability in vk_av1_decode_slice() in libavcodec/vulkan_av1.c because the tile-count limit is checked only on entry. Attackers can supply a crafted AV1 stream with more than 256 tiles decoded via the Vulkan hardware accelerator to overflow tile_sizes and corrupt heap memory.

CVSS 4.0 · 7.3 High EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125198

FFmpeg through 9.0.2 Memory Leak via MediaCodec JNI setBuffer

FFmpeg through 9.0.2 contains a memory leak vulnerability in mediaformat_jni_setBuffer() in libavcodec/mediacodec_wrapper.c that never frees buffers wrapped with NewDirectByteBuffer(). Attackers can supply crafted media files with large extradata, leaking native memory on each MediaCodec decoder configuration in Android applications and causing resource exhaustion.

CVSS 4.0 · 2 Low EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125197

FFmpeg through 9.0.2 Heap Out-of-Bounds Read via LCL/ZLIB Multithread Decoding

FFmpeg through 9.0.2 contains an integer underflow in decode_frame() in libavcodec/lcldec.c that allows attackers to trigger a heap out-of-bounds read via short ZLIB packets with FLAG_MULTITHREAD. Attackers can supply a crafted AVI or MKV file with an LCL video stream whose packet is shorter than 8 bytes, bypassing length clamping to crash the decoding application.

CVSS 4.0 · 6.9 Medium EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125193

FFmpeg through 9.0.2 Out-of-Bounds Read via bitpacked_decode_uyvy422()

FFmpeg through 9.0.2 contains an out-of-bounds read vulnerability in bitpacked_decode_uyvy422() in libavcodec/bitpacked_dec.c because it never verifies packets hold width * height * 2 bytes. Attackers can supply truncated bitpacked UYVY422 packets via crafted SDP/RFC 4175 RTP sessions or raw input to crash applications or expose adjacent heap memory.

CVSS 4.0 · 6.9 Medium EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg