Cyber Resilience

CVE-2021-33486

High

Published: 03 August 2021

Published
03 August 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0039 60.4th percentile
Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-33486 is a high-severity Improper Handling of Exceptional Conditions (CWE-755) vulnerability in Codesys Runtime Toolkit. Its CVSS base score is 7.5 (High).

Operationally, ranked in the top 39.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

All versions of the CODESYS V3 Runtime Toolkit for VxWorks from version V3.5.8.0 and before version V3.5.17.10 have Improper Handling of Exceptional Conditions.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

codesys
runtime toolkit
3.5.8.0 — 3.5.17.10

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-755

Provides defined handling (alert and additional actions) for the exceptional condition of audit logging failure.

addresses: CWE-755

Supplies a concrete handling action (safe mode) for exceptional conditions, mitigating risks from improper or absent handling that could allow continued attacks.

addresses: CWE-755

By preparing users for contingency scenarios, the control promotes proper handling of exceptional conditions instead of default or unsafe behaviors.

addresses: CWE-755

An updated contingency plan defines current actions for exceptional conditions, reducing the window for attackers to exploit improper handling leading to system failure.

addresses: CWE-755

Procedures ensure proper handling of exceptional conditions to support effective incident response.

addresses: CWE-755

Incident response testing confirms proper handling of exceptional conditions to limit exploit impact.

addresses: CWE-755

Gives users guidance on incident handling, reducing improper handling of exceptional conditions that could stem from exploited weaknesses.

addresses: CWE-755

Enforces structured response to exceptional conditions so the system cannot remain in an unsafe state.

References