# CVE-2026-44663: AcademySoftwareFoundation OpenEXR integer overflow in HTJ2K decoder

Source: https://junglewise.ai/threats/cve-2026-44663-academysoftwarefoundation-openexr-integer-overflow-in-htj2k  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-18. Updated: 2026-06-21  
License: CC BY 4.0 with a link back

CVE-2026-44663 · Severity: medium · CVSS 6.1 · Published 2026-06-18

OpenEXR is a standard library used in the motion picture industry for handling high-quality image files. A vulnerability in its image decoding component allows a specially crafted image file to cause a memory error. If a user opens such a file, it could lead to an application crash or potentially allow an attacker to gain unauthorized control over the system.

## Quick answers

**Is CVE-2026-44663 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-44663 being exploited in the wild.

**How severe is CVE-2026-44663?** Medium severity, with a CVSS score of 6.1, published 18 June 2026.

**Which products and versions are affected?** AcademySoftwareFoundation OpenEXR 3.4.0 through 3.4.11.

**Is there a fix for CVE-2026-44663?** A patch was published on 2026-05-25: Fixed in version 3.4.12 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-44663 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-44663?** Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

An integer overflow exists in the ht_undo_impl() function within src/lib/OpenEXRCore/internal_ht.cpp. The vulnerability is caused by 32-bit signed arithmetic when multiplying a channel's width (int32_t) by its bytes_per_element. When processing FLOAT data with widths exceeding 536,870,912, the resulting product overflows INT32_MAX, leading to a corrupted offset used in pointer arithmetic. This results in a heap-based out-of-bounds write during the decompression of HTJ2K-compressed EXR files. The issue is present in three distinct paths within the HTJ2K decoder: raster line offset calculation, bytes-per-line accumulation, and pixel-line pointer advancement. The vulnerability has been addressed in version 3.4.12 by casting operands to 64-bit integers before multiplication.

## Affected products

- AcademySoftwareFoundation OpenEXR 3.4.0 through 3.4.11

## Timeline

- 2026-05-25: patched: Fixed in version 3.4.12
- 2026-05-25: advisory: GitHub Security Advisory GHSA-777r-f9x8-7r84 published
- 2026-06-18: disclosed: CVE-2026-44663 published to NVD

## References

- [https://github.com/AcademySoftwareFoundation/openexr/releases/tag/v3.4.12](https://github.com/AcademySoftwareFoundation/openexr/releases/tag/v3.4.12)
- [https://github.com/AcademySoftwareFoundation/openexr/security/advisories/GHSA-777r-f9x8-7r84](https://github.com/AcademySoftwareFoundation/openexr/security/advisories/GHSA-777r-f9x8-7r84)