CVE Catalog

CVE-2026-125197

MediumCVSS 6.1
Published: Translated: NVD NIST

Summary

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.

Risk Assessment

This can lead to denial of service (DoS) or potential information disclosure through heap out-of-bounds read in applications decoding LCL files.

Recommendation

Update FFmpeg to a version later than 9.0.2 or apply available patches. Avoid processing untrusted AVI/MKV files with LCL streams until updated.

Other vulnerabilities in FFmpeg

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Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS