Bug 2455423 (CVE-2026-34378)

Summary: CVE-2026-34378 OpenEXR: OpenEXR: Denial of Service via crafted EXR file integer overflow
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in OpenEXR, a widely used image storage format. A remote attacker could exploit a missing bounds check vulnerability by crafting a malicious EXR file. By manipulating a specific attribute in the file header, an attacker can trigger an integer overflow, causing the application to unexpectedly terminate. This leads to a Denial of Service (DoS) for systems processing the malformed image file.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2455491, 2455492, 2455489, 2455493    
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Description OSIDB Bzimport 2026-04-06 16:03:59 UTC 
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.