What is CVE-2021-21867?

CVE-2021-21867 is a high-severity vulnerability in Codesys, classified under Deserialization of Untrusted Data. CVSS score: 7.8/10. Published 2021-08-18.

How severe is CVE-2021-21867?

High severity. CVSS v3 base score is 7.8 out of 10.

Deserialization in Codesys

CVE-2021-21867

An unsafe deserialization vulnerability exists in the ObjectManager.plugin ObjectStream.ProfileByteArray functionality of CODESYS GmbH CODESYS Development System 3.5.16 and 3.5.17. A specially crafted file can lead to arbitrary command execution. An attacker can provide a malicious file to trigger this vulnerability.

Vulnerability class: Insecure Deserialization

EPSS: 0.016 (74.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

Codesys — versions 3.5.16.0, 3.5.17.0
N/a Codesys — versions CODESYS GmbH CODESYS Development System 3.5.16, CODESYS GmbH CODESYS Development System 3.5.17

Weakness classification (CWE)

CWE-502 — Deserialization of Untrusted Data

References

talos-cna@cisco.com (Exploit, Third Party Advisory, x_refsource_MISC)
talos-cna@cisco.com (Patch, x_refsource_MISC, Mitigation, Vendor Advisory)

Frequently asked questions

What is CVE-2021-21867?: CVE-2021-21867 is a high-severity vulnerability in Codesys, classified under Deserialization of Untrusted Data. CVSS score: 7.8/10. Published 2021-08-18.
How severe is CVE-2021-21867?: High severity. CVSS v3 base score is 7.8 out of 10.