Out-of-bounds Read in Opencascade Open Cascade Technology
CVE-2026-42476
Two heap-based out-of-bounds read vulnerabilities in the STL ASCII file parser in Open CASCADE Technology (OCCT) V8_0_0_rc5 exist in RWStl_Reader::ReadAscii because buffers returned by Standard_ReadLineBuffer::ReadLine() are not properly length-validated before strncasecmp or direct byte access. User-assisted attackers can trigger these issues by persuading a victim to open a crafted STL file with extremely short lines, resulting in a denial of service or possible information disclosure.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H.
EPSS exploit prediction
EPSS: 0.001 (2.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 3rd percentile — 2.8% 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)
References
- gist.github.com/sgInnora/dfba083d04906283e9c92aea78e2d94a (Third Party Advisory)
Frequently asked questions
- What is CVE-2026-42476?
- CVE-2026-42476 is a high-severity vulnerability in Opencascade Open Cascade Technology, classified under Out-of-bounds Read. CVSS score: 7.1/10. Published 2026-05-01.
- How severe is CVE-2026-42476?
- High severity. CVSS v3 base score is 7.1 out of 10.