CVE-2026-34543: Openexr Security Vulnerability (CVSS 8.7)

OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From versions 3.0.0 to before 3.2.9, 3.3.0 to before 3.3.11, and 3.4.0 to before 3.4.11, IDManifest::init() reconstructs strings from a prefix-compressed representation. If the previous string is longer than 255 bytes, the next string is expected to begin with a 2-byte prefix length. The code reads stringList[i][0] and stringList[i][1] without checking that the current string has at least two bytes. This issue has been patched in versions 3.2.9, 3.3.11, and 3.4.11.

OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. In versions 3.4.0 through 3.4.9, 3.3.0 through 3.3.9, and 3.2.0 through 3.2.7, `internal_dwa_compressor.h:1040` performs `chan->width * chan->bytes_per_element` in `int32` arithmetic without a `(size_t)` cast. This is the same overflow pattern fixed in other decoders by CVE-2026-34589/34588/34544, but this line was missed. Versions 3.4.10, 3.3.10, and 3.2.8 contain a fix that addresses `internal_dwa_compressor.h:1040`.

OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. In versions 3.4.0 through 3.4.9, 3.3.0 through 3.3.9, and 3.2.0 through 3.2.7, `internal_dwa_compressor.h:1722` performs `curc->width * curc->height` in `int32` arithmetic without a `(size_t)` cast. This is the same overflow pattern fixed in other locations by the recent CVE-2026-34589 batch, but this line was missed. Versions 3.4.10, 3.3.10, and 3.2.8 contain a fix that addresses `internal_dwa_compressor.h:1722`.

OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.1.0 to before 3.2.7, 3.3.9, and 3.4.9, internal_exr_undo_piz() advances the working wavelet pointer with signed 32-bit arithmetic. Because nx, ny, and wcount are int, a crafted EXR file can make this product overflow and wrap. The next channel then decodes from an incorrect address. The wavelet decode path operates in place, so this yields both out-of-bounds reads and out-of-bounds writes. This vulnerability is fixed in 3.2.7, 3.3.9, and 3.4.9.

OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From version 3.4.0 to before version 3.4.7, an attacker providing a crafted .exr file with HTJ2K compression and a channel width of 32768 can write controlled data beyond the output heap buffer in any application that decodes EXR images. The write primitive is 2 bytes per overflow iteration or 4 bytes (by another path), repeating for each additional pixel past the overflow point. In this context, a heap write overflow can lead to remote code execution on systems. This issue has been patched in version 3.4.7.

OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From version 3.4.0 to before version 3.4.8, a crafted B44 or B44A EXR file can cause an out-of-bounds write in any application that decodes it via exr_decoding_run(). Consequences range from immediate crash (most likely) to corruption of adjacent heap allocations (layout-dependent). This issue has been patched in version 3.4.8.