OpenEXR is the reference implementation and specification for the EXR image format, widely used in the motion picture industry. In versions before 3.2.11, 3.3.0 through 3.3.12, and 3.4.0 through 3.4.13, exrmultiview can write past a heap allocation when it combines two attacker-supplied, individually valid scanline EXR files whose union dataWindow is not aligned to one view's channel subsampling. The utility allocates sampled channel storage using a truncated union_width / xSampling, then reads the sampled input through a Slice based on the misaligned union window, producing a heap out-of-bounds write. The trigger is normal public-tool processing, such as exrmultiview left A.exr right B.exr out.exr with crafted but valid inputs, so this is not solely an API or caller-precondition issue. This issue is fixed in versions 3.2.11, 3.3.13, and 3.4.14.
https://github.com/AcademySoftwareFoundation/openexr/security/advisories/GHSA-gjf7-wjjw-xq56
https://github.com/AcademySoftwareFoundation/openexr/commit/e2300a3d54a93d20a36a86b82f3a506c4c91476f
https://github.com/AcademySoftwareFoundation/openexr/commit/c644ac2dfeac82939c81a8551d6f4b7859f63add
https://github.com/AcademySoftwareFoundation/openexr/commit/77ee19c021398b1c56f32c3af8347e365dbd4f33