Vulnerability in CODESYS Development System 3

[ Description ]Official description

The CODESYS Gateway Client allocates memory based on a size field in a gateway response without enforcing an appropriate upper limit. An unauthenticated remote attacker controlling a malicious gateway can exploit this behavior to trigger excessive memory consumption, resulting in a denial-of-service condition thus leading to a total loss of availablity.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ Advisories ]Government CERT advisories

• BSI CERT-Bund1 Oct 2026WID-SEC-2026-3710

  CODESYS Control Runtime and Gateway Client: Multiple vulnerabilities Translated from German

  CVE-2026-79625CVE-2026-76992
• BSI CERT-Bund30 Sep 2026WID-SEC-2026-3688

  CODESYS Gateway Client: Vulnerability allows denial of service Translated from German

  CVE-2026-76992

[ References ]References

• www.certvde.com/en/advisories/VDE-2026-094