Description
OpenImageIO is a toolset for reading, writing, and manipulating image files of any image file format relevant to VFX / animation. Prior to 3.1.16.0, A crafted 1-bit contiguous cmyk tiff is exposed through a native uint1 imagespec, so callers allocate a bit-packed buffer. tiffinput::read_native_scanline_locked() nevertheless invokes tiffinput::bit_convert() with 8-bit output and writes one expanded byte per value into that smaller buffer, resulting in a heap out-of-bounds write and memory corruption. The affected implementation is identified by src/tiff.imageio/tiffinput.cpp, TIFFInput::bit_convert(), TIFFInput::read_native_scanline_locked(), PHOTOMETRIC_SEPARATED, 1-bit CMYK, and native uint1 ImageSpec, which define the relevant source path, functions, state, and trigger. This issue is fixed in 3.1.16.0.
Affected products
openimageio: openimageio
References5
- github.com/AcademySoftwareFoundation/OpenImageIO/security/advis… ExploitVendor Advisory
- github.com/AcademySoftwareFoundation/OpenImageIO/commit/6e9b86e… Patch
- github.com/AcademySoftwareFoundation/OpenImageIO/pull/5296 Issue TrackingPatch
- github.com/user-attachments/files/29615314/poc.zip Exploit
- github.com/AcademySoftwareFoundation/OpenImageIO/releases/tag/v… Release Notes
Metrics
- CVSS 3.1
-
7.6
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H - EPSS — exploit probability
- 0% percentile: 21 · as of 8 November 2026
- CWE
- CWE-122CWE-131CWE-787
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