CVE-2026-54920
Received
Received - Intake
Heap Overflow in OpenEXR HTJ2K Decoding
Vulnerability report for CVE-2026-54920, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-08-25
Last updated on: 2026-08-25
Assigner: GitHub, Inc.
Description
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 3.4.12, a reachable assertion failure in the HTJ2K decode path allows a crafted HTJ2K-compressed EXR file to cause an unconditional process abort in any application that calls exr_start_read() on untrusted input, resulting in denial of service. The crash is triggered by a QCD marker whose lower five bits are zero, which OpenEXR passes into the vendored OpenJPH library while constructing the codestream and evaluating its quantization delta parameters. OpenJPH uses an assertion rather than a recoverable error to validate those bits, so any invalid value calls abort() directly and cannot be intercepted by surrounding error handling, a problem compounded by OpenEXR wrapping only its internal HT header parser in error handling while leaving the later codestream read and construction calls unprotected. This issue has been resolved in version 3.4.13.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| academysoftwarefoundation | openexr | From 3.4.0 (inc) to 3.4.12 (inc) |
| academysoftwarefoundation | openexr | 3.4.13 |
| academysoftwarefoundation | openexrutil | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-190 | The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number. |
| CWE-824 | The product accesses or uses a pointer that has not been initialized. |
