CVE-2026-45696: academysoftwarefoundation openexr Heap-based Buffer Overflow

Vulnerability summary

CVE-2026-45696 is a high (CVSS 8.3) Heap-based Buffer Overflow vulnerability in academysoftwarefoundation openexr. EPSS estimates a 0.42% chance of exploitation in the next 30 days, higher than 34.7% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 18-06-2026
   PublishedVulnerability first disclosed.
2. 15-07-2026
   Last modifiedVulnerability information updated.

Description

OpenEXR is the reference implementation and specification for the EXR image format, widely used in the motion picture industry. In versions 3.4.0 through 3.4.11, the HTJ2K (High-Throughput JPEG 2000) decoder, ht_undo_impl() in OpenEXRCore is vulnerable to a heap-buffer-overflow READ. The ht_undo_imp function copies decoded pixels out of a per-line OpenJPH buffer using the EXR channel's declared width as the iteration count. The codestream embedded in the EXR chunk can declare different (smaller) tile/line dimensions than the EXR header advertises, but ht_undo_impl() does not validate this — it pulls width 32-bit samples from cur_line->i32[] without checking the OpenJPH line buffer's actual length. A crafted EXR file produces a 4-byte heap-buffer-overflow READ immediately after a buffer allocated by ojph::local::codestream::finalize_alloc(). The bug is reachable through the standard scanline-decode entry point used by every consumer of exr_decoding_run/Imf::checkOpenEXRFile, including thumbnailers, asset pipelines, and the exrcheck utility — i.e. any application that opens untrusted EXR files. The result is a deterministic crash (DoS) and potential adjacent-heap leak. This issue has been fixed in version 3.4.12.

• 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-125Out-of-bounds ReadThe product reads data past the end, or before the beginning, of the intended buffer.