How severe is CVE-2021-33486?

CVE-2021-33486 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-33486 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33486?

CVE-2021-33486 affects Codesys Runtime Toolkit. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-33486?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-33486 published?

CVE-2021-33486 was published on 2021-08-03 and last updated on 2026-06-17.

CVE-2021-33486

CVE-2021-33486 is a high-severity vulnerability in Codesys Runtime Toolkit with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-755.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-755
Affected product: Codesys Runtime Toolkit
Published: 2021-08-03
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2021-33486?: 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.
How severe is CVE-2021-33486?: CVE-2021-33486 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-33486 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33486?: CVE-2021-33486 affects Codesys Runtime Toolkit. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-33486?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-33486 published?: CVE-2021-33486 was published on 2021-08-03 and last updated on 2026-06-17.

References

https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=14806&token=637e12e86301b83beac1653bd88da3aa5aa3f51b&download=

Affected products (1)

cpe:2.3:a:codesys:runtime_toolkit:*:*:*:*:*:vxworks:*:*

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