Heap out-of-bounds write via pointer overflow
Published Apr 6, 2026 · Updated Apr 6, 2026
Heap out-of-bounds write in OpenEXR's DWA lossy decoder allows attackers to corrupt memory via crafted scanline DWAA files. In internal_dwa_decoder.h, numBlocksX * 64 uses signed int arithmetic, wraps at a large image width, and derives component pointers outside rowBlockHandle. Exploitation requires a user or user-initiated process to decode the file; the demonstrated consequence is a write-side process crash.
Summary
What happened
Heap out-of-bounds write in OpenEXR's DWA lossy decoder allows attackers to corrupt memory via crafted scanline DWAA files. In internal_dwa_decoder.h, numBlocksX * 64 uses signed int arithmetic, wraps at a large image width, and derives component pointers outside rowBlockHandle. Exploitation requires a user or user-initiated process to decode the file; the demonstrated consequence is a write-side process crash.
The record
- CVE
- CVE-2026-34589
- Published
- Apr 6, 2026
- Updated
- Apr 6, 2026
- Vendor
- Academy Software Foundation
- Product
- OpenEXR
- Classifications
- CWE-190, CWE-787, T1203
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 6, 2026CVE publishedPublication date reported by the CVE source.
- Apr 6, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=>= 3.2.0, < 3.2.7
- Affected versionversion=>= 3.3.0, < 3.3.9
- Affected versionversion=>= 3.4.0, < 3.4.9
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- dwa_scanline_exrcheck.zipproof of concept · demonstrated
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Technologies
Your stack
See the directory against your own environment.
Your stack
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