CVE-2026-63422: academysoftwarefoundation openimageio Heap-based Buffer Overflow

Vulnerability summary

CVE-2026-63422 is a high (CVSS 7.8) Heap-based Buffer Overflow vulnerability in academysoftwarefoundation openimageio. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 10% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 18-09-2026
   PublishedVulnerability first disclosed.
2. 21-09-2026
   Last modifiedVulnerability information updated.

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 valid tiled openexr image whose width is not a multiple of its tile width can trigger an overflow when a caller reads a partial edge-tile rectangle. openexrinput::read_native_tiles() copies each row into the caller buffer using the padded whole-tile scanline_stride rather than user_scanline_bytes for the requested rectangle, resulting in a heap out-of-bounds write and memory corruption. The affected implementation is identified by src/openexr.imageio/exrinput.cpp, OpenEXRInput::read_native_tiles(), partial edge tile, user_scanline_bytes, and scanline_stride, 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.

• CWE-122Heap-based Buffer OverflowA heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
• CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.