CVE-2026-63638
Prior to 3.0.21.0, 3.1.16.0, and 3.2.0.3-beta1, A crafted cineon image can declare unsupported component bit depth 26. cineoninput::open() maps it to a 32-bit imagespec, but libcineon maps the unsupported depth to an 8-byte value, so…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.46%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
OpenImageIO is a toolset for reading, writing, and manipulating image files of any image file format relevant to VFX / animation. Prior to 3.0.21.0, 3.1.16.0, and 3.2.0.3-beta1, A crafted cineon image can declare unsupported component bit depth 26. cineoninput::open() maps it to a 32-bit imagespec, but libcineon maps the unsupported depth to an 8-byte value, so cineoninput::read_native_scanline() causes attacker-controlled data to be written beyond the 4-byte-per-pixel caller buffer, resulting in a heap out-of-bounds write and memory corruption. The affected implementation is identified by src/cineon.imageio/cineoninput.cpp, CineonInput::open(), CineonInput::read_native_scanline(), ComponentDataSize(), bit depth 26, and ImageSpec, which define the relevant source path, functions, state, and trigger. This issue is fixed in versions 3.0.21.0, 3.1.16.0, and 3.2.0.3-beta1.
- CVSS 3.1
- 8.3 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:H
- EPSS
- 0.46% probability · 40th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-787
- Affected
- openimageio/openimageio
- Source
- security-advisories@github.com
EPSS 0.5% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/AcademySoftwareFoundation/OpenImageIO/commit/6f2b2e85b3b3933ccc5a46303d5535f99bfa39fbPatch
- https://github.com/AcademySoftwareFoundation/OpenImageIO/pull/5283Issue Tracking, Patch
- https://github.com/AcademySoftwareFoundation/OpenImageIO/releases/tag/v3.0.21.0Release Notes
- https://github.com/AcademySoftwareFoundation/OpenImageIO/releases/tag/v3.1.16.0Release Notes
- https://github.com/AcademySoftwareFoundation/OpenImageIO/security/advisories/GHSA-9hxv-jvgr-3x8gExploit, Mitigation, Vendor Advisory
- https://github.com/AcademySoftwareFoundation/OpenImageIO/security/advisories/GHSA-9hxv-jvgr-3x8gExploit, Mitigation, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.