CVE-2026-42481
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedOpen CASCADE Technology (OCCT) V8_0_0_rc5 contains multiple vulnerabilities in its IGES and STEP file parsers that can be triggered by crafted IGES or STEP files. These issues include an out-of-bounds read in Geom2d_BSplineCurve::EvalD0 during IGES B-spline curve evaluation, an out-of-bounds read in MakeBSplineCurveCommon during STEP B-spline curve construction, and infinite recursion in StepShape_OrientedEdge::EdgeStart when processing a self-referential OrientedEdge entity. Successful exploitation may result in denial of service or unintended memory disclosure.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceOpen CASCADE Technology V8_0_0_rc5 contains three vulnerabilities in its IGES and STEP file parsers: an out-of-bounds read in Geom2d_BSplineCurve::EvalD0 during IGES B-spline evaluation, an out-of-bounds read in MakeBSplineCurveCommon during STEP B-spline curve construction, and infinite recursion in StepShape_OrientedEdge::EdgeStart when processing self-referential OrientedEdge entities. All three are triggered by parsing crafted malicious CAD files and can cause denial of service or memory disclosure.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data<= 7.9.3= 8.0.0CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Identify Open CASCADE Technology versionCheck the installed OCCT version by looking at the product documentation, library metadata, or using the application's about/version information. Common locations: /usr/include/opencascade/version.h, or check the shared library version (libTKSTEP.so, libTKIGES.so on Linux).Affected if The installed version is 7.9.3 or lower, or exactly 8.0.0
-
Determine if IGES file parser is in useCheck if your application or system loads the IGES module (libTKIGES.so on Linux, TKIGES.dll on Windows) or processes .iges, .igs files. Review application dependencies or process monitoring.Affected if IGES file processing is enabled and the application loads the IGES parsing module
-
Determine if STEP file parser is in useCheck if your application or system loads the STEP module (libTKSTEP.so on Linux, TKSTEP.dll on Windows) or processes .step, .stp files. Review application dependencies or process monitoring.Affected if STEP file processing is enabled and the application loads the STEP parsing module
-
Assess exposure to untrusted CAD filesReview whether your OCCT-based application accepts IGES or STEP files from untrusted or external sources, or processes files in any automated workflow.Affected if The application processes IGES or STEP files from untrusted or external sources without validation
A user is affected if their Open CASCADE Technology version is 7.9.3 or lower, or exactly 8.0.0, AND they process IGES or STEP files in their application.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataAvoid opening untrusted IGES and STEP files in OCCT-based applications; implement file validation and sandboxing for CAD file processing.
- Consultation3.0 h
- Implementation8.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,800.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-42481 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-42481 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data