CVE-2021-36764

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-08-04 · updated 2026-06-17
Weakness: CWE-476

Description

In CODESYS Gateway V3 before 3.5.17.10, there is a NULL Pointer Dereference. Crafted communication requests may cause a Null pointer dereference in the affected CODESYS products and may result in a denial-of-service condition.

Affected products

CODESYS Gateway Server V2: from 3.0 before 3.5.17.10 — fixed in 3.5.17.10

How to fix

Upgrade to a fixed version: CODESYS Gateway Server V2 3.5.17.10. Check the vendor advisory for mitigations.

References

https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16804&token=d8c89c887979b22fdfc9fd5c3aa3804bbb1ddbff&download=
https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16804&token=d8c89c887979b22fdfc9fd5c3aa3804bbb1ddbff&download=

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