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CVE Record

CVE-2026-42216: OpenEXR: Out-of-bounds read in `IDManifest::init()` during prefix expansion

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.

HighCVSS 8.8Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

OpenEXR can mishandle specially formed EXR image metadata and read beyond expected memory. For businesses, the main concern is services or tools that automatically process EXR files, especially from users, partners, or shared media pipelines.

Executive priority

Treat as high priority where EXR files enter automated workflows or customer-facing upload paths. Lower priority may be reasonable for isolated systems that do not parse EXR content, but version inventory is still required.

Technical view

In affected OpenEXR releases, IDManifest::init() reconstructs prefix-compressed strings and reads two prefix-length bytes without first confirming the current string contains two bytes. Sources classify this as CWE-125 and CWE-130 with CVSS 4.0 score 8.8.

Likely exposure

Exposure is most likely in rendering, media-processing, image-conversion, asset-ingest, or security-scanning workflows that use OpenEXR 3.x and parse EXR files. Downstream Linux packages may also be affected depending on distribution packaging.

Exploitation context

The supplied sources do not report active exploitation, and the CVE is not marked KEV. The issue appears reachable through crafted EXR content, but the bundle does not provide exploit maturity or proof-of-concept details.

Researcher notes

The key condition is prefix expansion after a previous string exceeds 255 bytes, followed by a too-short current string. The bundle confirms patched upstream versions but does not include crash behavior, exploit reliability, or product-specific reachability.

Mitigation direction

  • Upgrade OpenEXR to 3.2.9, 3.3.11, 3.4.11, or later as applicable.
  • Apply Red Hat errata for affected Red Hat-distributed packages.
  • Identify third-party products that bundle OpenEXR and request vendor-fixed builds.
  • Prioritize patching systems that process externally supplied EXR files.
  • Check vendor guidance where OpenEXR is statically linked or embedded.

Validation and detection

  • Inventory installed OpenEXR versions across servers, workstations, containers, and build images.
  • Check package manager output against the affected version ranges.
  • Review media-processing services for EXR upload or conversion paths.
  • Confirm Red Hat systems have the referenced RHSA updates applied.
  • Verify embedded dependencies with SBOMs or build manifests.
Prepared
Confidence
high
Sources
12

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-125: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cwe · low confidence lookup

CWE-130: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2026-42216 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
High
CVSS
8.8 (4.0)
Known Exploited
No
Published

Vector: 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

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

2CVSS vectors
5Timeline events
2ADP providers
11Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: pocAutomatable: yesTechnical Impact: partial

CVSS vector scores

2 official scores

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
8.8CVSS 4.0HighCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N——GitHub_M
8.1CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H2.85.2redhat-SADP

Vulnerability scoring details

Base CVSS 4.0 score

8.8High
CVSS 4.0 vector shape for CVE-2026-42216Attack VectorAttack ComplexityAttack RequirementsPrivileges RequiredUser InteractionVS ConfidentialityVS IntegrityVS AvailabilitySS ConfidentialitySS IntegritySS Availability

Vector: 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

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Attack Requirements
NonePresent
Privileges Required
NoneLowHigh
User Interaction
NonePassiveActive
VS Confidentiality
HighLowNone
VS Integrity
HighLowNone
VS Availability
HighLowNone
SS Confidentiality
HighLowNone
SS Integrity
HighLowNone
SS Availability
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. ADP timelineredhat-SADP

    Made public.

  3. CVE publishedCVE Program

    The CVE record was published.

  4. ADP timelineredhat-SADP

    Reported to Red Hat.

  5. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc
redhat-SADPOpenEXR: OpenEXR: Information disclosure and denial of service via malformed EXR files
other:Red Hat severity ratingcvssV3_1
  • 2026-05-07T05:02:12.164Z: Reported to Red Hat.
  • 2026-05-07T04:01:59.602Z: Made public.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
AcademySoftwareFoundationopenexr>= 3.0.0, < 3.2.9, >= 3.3.0, < 3.3.11, >= 3.4.0, < 3.4.11Listed
Weakness

CWE details

CWE-125CWE-130

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-125 · source CWE mapping

Out-of-bounds Read

Out-of-bounds Read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs
CWE-130 · source CWE mapping

Improper Handling of Length Parameter Inconsistency

Improper Handling of Length Parameter Inconsistency represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs