OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.4.0 to before 3.4.9, a missing bounds check on the dataWindow attribute in EXR file headers allows an attacker to trigger a signed integer overflow in generic_unpack(). By setting dataWindow.min.x to a large negative value, OpenEXRCore computes an enormous image width, which is later used in a signed integer multiplication that overflows, causing the process to terminate with SIGILL via UBSan. This vulnerability is fixed in 3.4.9.
History

Tue, 07 Apr 2026 20:45:00 +0000

Type Values Removed Values Added
First Time appeared Openexr
Openexr openexr
CPEs cpe:2.3:a:openexr:openexr:*:*:*:*:*:*:*:*
Vendors & Products Openexr
Openexr openexr

Tue, 07 Apr 2026 07:15:00 +0000


Tue, 07 Apr 2026 00:00:00 +0000

Type Values Removed Values Added
First Time appeared Academysoftwarefoundation
Academysoftwarefoundation openexr
Vendors & Products Academysoftwarefoundation
Academysoftwarefoundation openexr
References
Metrics threat_severity

None

threat_severity

Moderate


Mon, 06 Apr 2026 16:45:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Mon, 06 Apr 2026 15:30:00 +0000

Type Values Removed Values Added
Description OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.4.0 to before 3.4.9, a missing bounds check on the dataWindow attribute in EXR file headers allows an attacker to trigger a signed integer overflow in generic_unpack(). By setting dataWindow.min.x to a large negative value, OpenEXRCore computes an enormous image width, which is later used in a signed integer multiplication that overflows, causing the process to terminate with SIGILL via UBSan. This vulnerability is fixed in 3.4.9.
Title OpenEXR has a signed integer overflow in generic_unpack() when parsing EXR files with crafted negative dataWindow.min.x
Weaknesses CWE-190
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-04-06T15:19:34.871Z

Updated: 2026-04-07T03:07:17.341Z

Reserved: 2026-03-27T13:43:14.370Z

Link: CVE-2026-34378

cve-icon Vulnrichment

Updated: 2026-04-06T15:33:03.523Z

cve-icon NVD

Status : Analyzed

Published: 2026-04-06T16:16:35.057

Modified: 2026-04-07T19:05:27.463

Link: CVE-2026-34378

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-04-06T15:19:34Z

Links: CVE-2026-34378 - Bugzilla