CVE-2026-34588 — OpenEXR has a signed 32-bit Overflow in PIZ Decoder Leads to OOB Read/Write

Description (CNA)

OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.1.0 to before 3.2.7, 3.3.9, and 3.4.9, internal_exr_undo_piz() advances the working wavelet pointer with signed 32-bit arithmetic. Because nx, ny, and wcount are int, a crafted EXR file can make this product overflow and wrap. The next channel then decodes from an incorrect address. The wavelet decode path operates in place, so this yields both out-of-bounds reads and out-of-bounds writes. This vulnerability is fixed in 3.2.7, 3.3.9, and 3.4.9.

Affected (CNA)

Vendor / product	Versions
AcademySoftwareFoundation / openexr	affected >= 3.1.0, <= 3.1.13; affected >= 3.2.0, < 3.2.7; affected >= 3.3.0, < 3.3.9; affected >= 3.4.0, < 3.4.9

CWE

CWE-125, CWE-190, CWE-787

References

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.

redhat-SADP

A flaw was found in OpenEXR, an image storage format for the motion picture industry. A remote attacker could exploit an integer overflow vulnerability in the `internal_exr_undo_piz()` function by providing a specially crafted EXR file. This flaw leads to out-of-bounds reads and writes, which may allow for arbitrary code execution or sensitive information disclosure.