CVE-2026-34380Public exploitNetwork attack vector

Decoder crash via PXR24 integer overflow

Published Apr 6, 2026 · Updated Apr 6, 2026

Integer overflow in OpenEXR 3.2.0 through 3.2.6, 3.3.0 through 3.3.8, and 3.4.0 through 3.4.8 allows attackers to crash decoders. The undo_pxr24_impl function multiplies a channel width by three as a signed 32-bit integer before casting, so wraparound can make its output-buffer bounds check accept an undersized allocation. Triggering requires an application to decode a crafted PXR24-compressed EXR file with a FLOAT channel; an ensuing out-of-bounds write is theoretical, while a sanitizer-detected crash is demonstrated.

CVSS severity5.9
Medium
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Integer overflow in OpenEXR 3.2.0 through 3.2.6, 3.3.0 through 3.3.8, and 3.4.0 through 3.4.8 allows attackers to crash decoders. The undo_pxr24_impl function multiplies a channel width by three as a signed 32-bit integer before casting, so wraparound can make its output-buffer bounds check accept an undersized allocation. Triggering requires an application to decode a crafted PXR24-compressed EXR file with a FLOAT channel; an ensuing out-of-bounds write is theoretical, while a sanitizer-detected crash is demonstrated.

The record

CVE
CVE-2026-34380
Published
Apr 6, 2026
Updated
Apr 6, 2026
Vendor
Academy Software Foundation
Product
OpenEXR
Classifications
CWE-787, CWE-190, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 6, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 6, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 3.2.0, < 3.2.7
  2. Affected versionversion=>= 3.3.0, < 3.3.9
  3. Affected versionversion=>= 3.4.0, < 3.4.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Academy Software Foundation · OpenEXRversion=>= 3.2.0, < 3.2.7; version=>= 3.3.0, < 3.3.9; version=>= 3.4.0, < 3.4.9

Published CVSS scores

5.9GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:H

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-787Out-of-bounds Write
CWE-190Integer Overflow or Wraparound
T1203Exploitation for Client Execution

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo