openexr: Out-of-bounds Read
CVE-2026-42216 is a critical-severity out-of-bounds read vulnerability in openexr from AcademySoftwareFoundation, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected openexr versions: >= 3.0.0, < 3.2.9; >= 3.3.0, < 3.3.11; >= 3.4.0, < 3.4.11. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.46% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of openexr you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| AcademySoftwareFoundation | openexr | >= 3.0.0, < 3.2.9; >= 3.3.0, < 3.3.11; >= 3.4.0, < 3.4.11 | Not stated |
| Red Hat | Red Hat Enterprise Linux 10 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 9 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 6 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 7 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 8 | Not specified in the record | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.8 | High | CNA (github.com) |
| CVSS 3.1 | 9.1 | Critical | NVD |
| CVSS 3.1 | 8.1 | High | CNA |
Official description
OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From versions 3.0.0 to before 3.2.9, 3.3.0 to before 3.3.11, and 3.4.0 to before 3.4.11, IDManifest::init() reconstructs strings from a prefix-compressed representation. If the previous string is longer than 255 bytes, the next string is expected to begin with a 2-byte prefix length. The code reads stringList[i][0] and stringList[i][1] without checking that the current string has at least two bytes. This issue has been patched in versions 3.2.9, 3.3.11, and 3.4.11.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Read
The product reads data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- Use a language that provides appropriate memory abstractions.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other references
- access.redhat.com/errata/RHSA-2026:38498
- access.redhat.com/errata/RHSA-2026:38499
- access.redhat.com/errata/RHSA-2026:39024
- access.redhat.com/errata/RHSA-2026:39025
- access.redhat.com/errata/RHSA-2026:39026
- access.redhat.com/errata/RHSA-2026:39027
- access.redhat.com/security/cve/CVE-2026-42216
- bugzilla.redhat.com/show_bug.cgi?id=2467633
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42216.json
Other vulnerabilities in openexr
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
Recent Out-of-bounds Read vulnerabilities
- 7.5 High severity
- 8.8 High severity
- 8.1 High severity
- 8.8 High severity
- 7.1 High severity
- 7.1 High severity
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