What is CVE-2026-42479?

CVE-2026-42479 is a medium-severity vulnerability in Opencascade Open Cascade Technology, classified under Out-of-bounds Read. CVSS score: 5.5/10. Published 2026-05-01.

How severe is CVE-2026-42479?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Out-of-bounds Read in Opencascade Open Cascade Technology

CVE-2026-42479

An out-of-bounds read vulnerability in VrmlData_IndexedLineSet::TShape in the VRML parser in Open CASCADE Technology (OCCT) V8_0_0_rc5 allows attackers to cause a denial of service via a crafted VRML file. The issue occurs because coordIndex values from parsed input are used as direct array indices without validation against the size of the coordinate array during geometry processing.

Vulnerability class: Buffer Overflow

Published 2026-05-01 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.001 (2.4th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 2nd percentile — 2.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: +0.000

Affected products

Opencascade Open Cascade Technology — versions 8.0.0

Weakness classification (CWE)

CWE-125 — Out-of-bounds Read

References

gist.github.com/sgInnora/dfba083d04906283e9c92aea78e2d94a (Third Party Advisory)

Frequently asked questions

What is CVE-2026-42479?: CVE-2026-42479 is a medium-severity vulnerability in Opencascade Open Cascade Technology, classified under Out-of-bounds Read. CVSS score: 5.5/10. Published 2026-05-01.
How severe is CVE-2026-42479?: Medium severity. CVSS v3 base score is 5.5 out of 10.