CVE-2026-65979 AcademySoftwareFoundation CVE debrief

Who should care

Defenders responsible for systems that use OpenEXR, such as those in the motion picture industry, should be aware of this vulnerability and take steps to update OpenEXR to version 3.4.13 or later.

Why it matters

CVE-2026-65979 is a vulnerability in OpenEXR that can lead to out-of-bounds reads when decoding untrusted files. Defenders should prioritize updating OpenEXR to version 3.4.13 or later to prevent potential out-of-bounds reads.

• Potential out-of-bounds reads when decoding untrusted files
• Possible crashes or data corruption
• Need to update OpenEXR to version 3.4.13 or later to prevent vulnerability

Technical summary

The HTJ2K decoder in OpenEXR versions 3.4.0 through 3.4.12 does not check if the header-length field (PLEN) fits within the available buffer before using it. This can lead to an out-of-bounds read when decoding untrusted files. The vulnerability is caused by the HTJ2K decoder parsing a header-length field from a chunk's compressed data without checking if it fits within the available buffer. This can lead to an out-of-bounds read when decoding untrusted files. Defenders should prioritize updating OpenEXR to version 3.4.13 or later to prevent potential out-of-bounds reads when decoding untrusted files.

Defensive priority

Defenders should prioritize updating OpenEXR to version 3.4.13 or later to prevent potential out-of-bounds reads when decoding untrusted files.

Recommended defensive actions

• Update OpenEXR to version 3.4.13 or later
• Verify that all instances of OpenEXR are updated to the latest version
• Monitor for any suspicious activity related to OpenEXR files
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The vulnerability is caused by the HTJ2K decoder parsing a header-length field from a chunk's compressed data without checking if it fits within the available buffer. This can lead to an out-of-bounds read when decoding untrusted files.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.