CVE-2026-42216Public exploitNetwork attack vector

Heap disclosure or crash via unchecked prefix length

Published May 7, 2026 · Updated May 7, 2026

Out-of-bounds read in OpenEXR allows remote attackers to disclose heap data or crash a process through a crafted EXR file. IDManifest::init() treats an empty prefix-compressed string as a two-byte prefix and reads the second byte beyond the heap buffer; the resulting length drives substring reconstruction. Reaching manifest parsing requires processing the crafted file, and heap disclosure additionally requires attacker control of adjacent heap layout; the demonstrated alternative is a process crash.

CVSS severity8.8
High
EPSS probability0.46%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds read in OpenEXR allows remote attackers to disclose heap data or crash a process through a crafted EXR file. IDManifest::init() treats an empty prefix-compressed string as a two-byte prefix and reads the second byte beyond the heap buffer; the resulting length drives substring reconstruction. Reaching manifest parsing requires processing the crafted file, and heap disclosure additionally requires attacker control of adjacent heap layout; the demonstrated alternative is a process crash.

The record

CVE
CVE-2026-42216
Published
May 7, 2026
Updated
May 7, 2026
Vendor
Academy Software Foundation
Product
OpenEXR
Classifications
CWE-130, CWE-125, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 7, 2026CVE publishedPublication date reported by the CVE source.
  2. May 7, 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.

  1. Affected versionversion=>= 3.0.0, < 3.2.9
  2. Affected versionversion=>= 3.3.0, < 3.3.11
  3. Affected versionversion=>= 3.4.0, < 3.4.11

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Academy Software Foundation · OpenEXRversion=>= 3.0.0, < 3.2.9; version=>= 3.3.0, < 3.3.11; version=>= 3.4.0, < 3.4.11

Published CVSS scores

9.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
8.1redhat-SADPCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H
8.8GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N

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-130Improper Handling of Length Parameter Inconsistency
CWE-125Out-of-bounds Read
T1499.004Application or System Exploitation

Public exploit references

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

Technologies

Your stack

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Your stack

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