CVE-2026-55371OpenEXR: OpenEXRCore exr_attr_set_bytes() accepts NULL type_hint with positive hint_length

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.

CVSS

6.9 MEDIUM (v4.0, CNA)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

Weakness (CWE)

CWE-20, CWE-476

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

Not loaded for this CVE

Assigned by

GitHub_M

NVD analysis

Deferred

Record last updated

Aug 25, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

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