CVE-2026-45696: OpenEXR is the reference implementation and specification for the EXR image format, widely used in the motion picture industry. In versions 3.4.0 thro...

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.

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS 4.0

8.3/10

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Probability

0.29%

20.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-122

Affected Software

Vendor	Product	Versions
Openexr	Openexr	>= 3.4.0, < 3.4.12

References

https://github.com/AcademySoftwareFoundation/openexr/releases/tag/v3.4.12Release Notes
https://github.com/AcademySoftwareFoundation/openexr/security/advisories/GHSA-gjpj-qv64-vwhfExploit, Vendor Advisory
https://github.com/AcademySoftwareFoundation/openexr/security/advisories/GHSA-gjpj-qv64-vwhfExploit, Vendor Advisory

Timeline

Published: Jun 18, 2026
Last Modified: Jun 26, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-45696?

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.

How severe is CVE-2026-45696?

CVE-2026-45696 has a CVSS score of 8.3/10 (HIGH severity). The EPSS model estimates a 0.29% probability of exploitation in the next 30 days.

How do I fix CVE-2026-45696?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.