8.8

CVE-2021-21867: codesys Deserialization of Untrusted Data

CVSS: 8.8v3.0HighModified
Published 18-08-2021Last modified 03-08-2024
Open JSON

Vulnerability summary

CVE-2021-21867 is a high (CVSS 8.8) Deserialization of Untrusted Data vulnerability in codesys. EPSS estimates a 1.78% chance of exploitation in the next 30 days, higher than 77.8% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
46/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.8/10
010
High · v3.0 (CVE.org)
EPSS score
1.78%
0%100%
Low · +0.13 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1reference

Timeline

  1. 18-08-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

4 scores · 2 sources · 3 versions

EPSS trend

Probability

1.78%

Chance of exploitation in the next 30 days

Percentile

78%

Versus all other CVEs

30-day change

+0.13 pp

From 1.65% on 19-09-2026

19-09-202619-10-2026
EPSS score
1.78%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • referenceUnverified

    Exploit Reference (talosintelligence.com)

    Maturity: unknown

Weaknesses

CWE · root cause

Affected systems

Codesys1 product

1 vendor · 1 product

References

2 links