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.
History

Thu, 18 Jun 2026 21:15:00 +0000

Type Values Removed Values Added
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.
Title OpenEXR HTJ2K decoder heap buffer over-read in ht_undo_impl() (DoS)
Weaknesses CWE-122
References
Metrics cvssV4_0

{'score': 8.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-06-18T20:31:56.603Z

Reserved: 2026-05-13T04:38:01.164Z

Link: CVE-2026-45696

cve-icon Vulnrichment

No data.

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-06-18T22:30:16Z