CVE Catalog

CVE-2026-70631

MediumCVSS 5.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.14%

3th percentile - higher than 3% of all known CVEs

Summary

In FFmpeg versions from 0.5 up to, but not including, 9.0, there is an uninitialized heap memory disclosure vulnerability in the native TIFF decoder in libavcodec/tiff.c. An attacker can supply a crafted TIFF file with a valid Deflate-compressed strip that terminates successfully after producing fewer bytes than declared. The tiff_unpack_zlib() 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.

Risk Assessment

This can lead to disclosure of sensitive heap memory data in services processing video, posing a confidentiality risk.

Recommendation

Update FFmpeg to version 9.0 or later which includes the fix.

Other vulnerabilities in FFmpeg

See all
Original NVD description (English source)

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 tiff_unpack_zlib() 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.

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