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TI-2021-04912 Aliases CVE-2021-21867GHSA-847p-f9h7-f5x2

Deserialization of untrusted data in CODESYS

Priority LOW 38CWE-502Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-502.

Summary

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.

Why it matters now

EPSS 0.01768 78th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
—CODESYSCODESYS GmbH CODESYS Development System 3.5.16, CODESYS GmbH CODESYS Development System 3.5.17—No fix listedCNA
  • CODESYS Vendor— Affected CODESYS GmbH CODESYS Development System 3.5.16, CODESYS GmbH CODESYS Development System 3.5.17 Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:codesys:codesys:3.5.16.0:*:*:*:*:*:*:*3.5.16.0VulnerableCODESYS
cpe:2.3:a:codesys:codesys:3.5.17.0:*:*:*:*:*:*:*3.5.17.0VulnerableCODESYS
  • cpe:2.3:a:codesys:codesys:3.5.16.0:*:*:*:*:*:*:* Versions 3.5.16.0 Vulnerable ·CODESYS
  • cpe:2.3:a:codesys:codesys:3.5.17.0:*:*:*:*:*:*:* Versions 3.5.17.0 Vulnerable ·CODESYS

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-21867
  2. 2026-10-03 Alias added: GHSA-847p-f9h7-f5x2

References

Exploit 1

Patch 1

  • TI-2021-13604 CODESYS V2 web server: crafted requests could trigger a null pointer dereference (DoS) CVSS 3.1HIGH 7.5
  • TI-2019-12244 CODESYS V2.3 ENI server up to V3.2.2.24 has a Buffer Overflow. CVSS 3.1CRITICAL 9.8
  • TI-2021-13601 CODESYS V2 web server: crafted requests could trigger a heap-based buffer overflow (DoS) CVSS 3.1HIGH 7.5
  • TI-2021-13602 CODESYS V2 web server: crafted requests could trigger a buffer over-read (DoS) CVSS 3.1CRITICAL 9.1
  • TI-2019-10170 3S-Smart Software Solutions GmbH CODESYS V3 Library Manager, all versions prior to… CVSS 3.1HIGH 8.6
  • TI-2021-04914 Deserialization of untrusted data in CODESYS CVSS 3.1HIGH 7.8
See all 12 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences