CVE-2021-25673 json
A vulnerability has been identified in SIMATIC S7-PLCSIM V5.4 (All versions).
published 2021-03-15 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-12565
- cvss
- 5.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 14%
- public exploits
- 0
- none known
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.
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
cisa ICSA-21-068-01 updated cvss 5.5
Siemens SIMATIC S7-PLCSIM
-
Siemens SIMATIC S7-PLCSIM V5.4affected: mitigation
Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf
Exploit prediction
0.23% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 4.9 | AV:L/AC:L/Au:N/C:N/I:N/A:C |
Affected products
- Siemens SIMATIC S7-PLCSIM V5.4
Classification
- Weakness
-
- CWE-835 Loop with Unreachable Exit Condition
References
-
cert-portal.siemens.com
/productcert/pdf/ssa-256092.pdf
vendor-advisory
Sources
- CVE List CVE-2021-25673
- NVD CVE-2021-25673
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