CVE intelligence and bounded remediation
CVE-2021-37172 — A vulnerability has been identified in SIMATIC S7-1200 CPU family (incl
A vulnerability has been identified in SIMATIC S7-1200 CPU family (incl. SIPLUS variants) (V4.5.0). Affected devices fail to authenticate against configured passwords when provisioned using TIA Portal V13. This could allow an attacker using TIA Portal V13 or later versions to bypass authentication and download arbitrary programs to the PLC. The vulnerability does not occur when TIA Portal V13 SP1 or any later version was used to provision the device.
- Severity
- High
- CVSS
- 7.5 (3.1)
- Published
- 2021-08-10
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-287
Affected products
- siemens / simatic_s7-1200_cpu_firmware / 4.5.0
- siemens / simatic_step_7_(tia_portal)
Matched remediation archetype
Authentication bypass and missing authentication
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Map every affected endpoint and protocol path, including alternate ports, legacy routes, recovery flows, service accounts, and machine-to-machine access.
- Confirm which deployments enable the affected authentication mode and whether the interface is reachable from untrusted networks.
- Review session, token, credential, and proxy trust configuration without attempting account takeover.
Remediate safely
- Apply the supported fix and centralize fail-closed authentication before protected request handling.
- Remove default or embedded credentials, rotate affected secrets and sessions, and bind authentication decisions to the intended audience and channel.
- Add negative tests for alternate routes, malformed or absent credentials, recovery flows, and proxy-derived identity.
Authoritative sources
Complete CVE record and remediation plan
The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.