Vulnerability · Published Aug 25, 2026 · Assigned by GitHub_M
CVE-2026-55371OpenEXR: OpenEXRCore exr_attr_set_bytes() accepts NULL type_hint with positive hint_length
Medium 6.9
In plain English
A medium-severity improper input validation in openexr from AcademySoftwareFoundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 6% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
OpenEXR is the reference implementation and specification for the EXR high-dynamic-range image file format, widely used in the motion picture industry. Versions 3.4.0 through 3.4.12 contain a NULL pointer dereference in the OpenEXRCore function exr_attr_set_bytes(). The public setter validates the top-level exr_attr_bytes_t value pointer but does not verify that the nested type_hint pointer is non-NULL when hint_length is greater than zero. When a caller supplies a positive hint_length together with a NULL type_hint, exr_attr_bytes_create() allocates a destination type-hint buffer and then copies from the NULL source pointer, causing a deterministic crash. The flaw is reachable through the public OpenEXRCore C API and results in a denial of service. The issue is fixed in version 3.4.13.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | openexr | no fix listed | DEBIAN-CVE-2026-55371 |
| Debian:13 | openexr | no fix listed | DEBIAN-CVE-2026-55371 |
| Debian:14 | openexr | 3.4.14-0.1 | DEBIAN-CVE-2026-55371 |
| Ubuntu:26.10 | openexr | no fix listed | UBUNTU-CVE-2026-55371 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| AcademySoftwareFoundation | openexr | >= 3.4.0, < 3.4.13 |
Weakness: CWE-20, CWE-476 · Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N