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TI-2021-07805 Aliases CVE-2021-25673GHSA-cxqw-29jq-pcjv

Infinite loop in Siemens SIMATIC S7-PLCSIM V5.4

Priority LOW 24CWE-835Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-835.

Summary

A vulnerability has been identified in SIMATIC S7-PLCSIM V5.4 (All versions). An attacker with local access to the system could cause a Denial-of-Service condition in the application when it is used to open a specially crafted file. As a consequence, the application could enter an infinite loop, become unresponsive and must be restarted to restore the service.

Why it matters now

EPSS 0.00231 14th percentileScored 2026-11-07
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
SiemensSIMATIC S7-PLCSIM V5.4All versions—No fix listedCNA
  • SIMATIC S7-PLCSIM V5.4 VendorSiemens Affected All versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:siemens:simatic_s7-plcsim:*:*:*:*:*:*:*:*all versionsVulnerableSiemens
  • cpe:2.3:a:siemens:simatic_s7-plcsim:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Siemens

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-25673
  2. 2026-10-03 Alias added: GHSA-cxqw-29jq-pcjv

References

Advisory 1

  • TI-2021-07807 A vulnerability has been identified in SIMATIC S7-PLCSIM V5.4 (All versions). CVSS 3.1MEDIUM 5.5
  • TI-2021-07806 NULL pointer dereference in Siemens SIMATIC S7-PLCSIM V5.4 CVSS 3.1MEDIUM 5.5

Sources

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