CVE-2026-42478
Published: 01 May 2026
Summary
CVE-2026-42478 is a high-severity NULL Pointer Dereference (CWE-476) vulnerability in Opencascade Open Cascade Technology. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 11.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-16 (Memory Protection).
Deeper analysis
CVE-2026-42478 affects the VRML V2.0 parser in Open CASCADE Technology (OCCT) version V8_0_0_rc5, specifically in the VrmlData_IndexedFaceSet::TShape component within the libTKDEVRML.so library. The vulnerability arises from malformed VRML input that triggers a dereference of a corrupt or unvalidated pointer during shape construction, leading to a denial of service. It is linked to CWE-476 (NULL Pointer Dereference) and CWE-125 (Out-of-bounds Read), with a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H), indicating high severity due to availability impact.
Attackers can exploit this vulnerability remotely over the network with low attack complexity, no required privileges, and no user interaction. By supplying a crafted VRML file to an application that processes VRML content using the affected OCCT parser, an attacker can cause a crash or resource exhaustion, resulting in denial of service on the targeted system.
Mitigation details are available in the referenced advisory at https://gist.github.com/sgInnora/dfba083d04906283e9c92aea78e2d94a.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-26601
Vulnerability details
An issue was discovered in VrmlData_IndexedFaceSet::TShape in the VRML V2.0 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 malformed VRML input can trigger dereference…
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of a corrupt or unvalidated pointer during shape construction in libTKDEVRML.so.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Vulnerability enables remote DoS via crafted VRML input causing crash/resource exhaustion in the parser, directly mapping to application/system exploitation for endpoint denial of service.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Requires validation of VRML inputs to block malformed files that trigger corrupt pointer dereferences in the OCCT parser.
Mandates timely remediation of the specific flaw in OCCT V8_0_0_rc5 VRML parser via patching to eliminate the pointer dereference vulnerability.
Implements memory safeguards like ASLR and DEP to protect against exploitation of NULL pointer dereferences and out-of-bounds reads during shape construction.