Denial of Service Vulnerability in Siemens SIMATIC S7-1200 CPU Devices
CVE-2011-20001
8.7HIGH
Key Information:
- Vendor
Siemens
- Status
- Vendor
- CVE Published:
- 14 October 2025
What is CVE-2011-20001?
A vulnerability exists in the web server interface of Siemens SIMATIC S7-1200 CPU devices, which fails to properly handle malformed HTTP requests when subjected to high traffic volumes. This issue permits an unauthenticated remote attacker to exploit the flaw, leading to the device entering a stop or defect state and causing denial of service. Users of SIMATIC S7-1200 CPU versions earlier than 2.0.3 are particularly susceptible, as the issue can disrupt operations and compromise system availability.
Affected Version(s)
SIMATIC S7-1200 CPU V1 family (incl. SIPLUS variants) 0
SIMATIC S7-1200 CPU V2 family (incl. SIPLUS variants) 0
References
CVSS V4
Score:
8.7
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None
Timeline
Vulnerability published
Vulnerability Reserved