CVE-2021-33737

HIGH
7.5
CVSS Score
Published: September 14, 2021 at 10:47 AM UTC
Updated: June 17, 2026 at 03:55 AM UTC
16 products affected across 1 vendorSIMATIC Cp 443-1 FirmwareSIMATIC Cp 343-1 FirmwareSIMATIC Cp 443-1 Advanced Firmware

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Severity
HIGH7.5
Exploit prediction
EPSS 1%

Description

A vulnerability has been identified in SIMATIC CP 343-1 (incl. SIPLUS variants) (All versions), SIMATIC CP 343-1 Advanced (incl. SIPLUS variants) (All versions), SIMATIC CP 343-1 ERPC (All versions), SIMATIC CP 343-1 Lean (incl. SIPLUS variants) (All versions), SIMATIC CP 443-1 (All versions < V3.3), SIMATIC CP 443-1 (All versions < V3.3), SIMATIC CP 443-1 Advanced (All versions < V3.3), SIPLUS NET CP 443-1 (All versions < V3.3), SIPLUS NET CP 443-1 Advanced (All versions < V3.3). Sending a specially crafted packet to port 102/tcp of an affected device could cause a denial of service condition. A restart is needed to restore normal operations.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

All versions
siemens-simatic-cp343-1-advanced (same device)
All versions
siemens-simatic-cp-343-1-erpc (same device)
All versions
siemens-simatic-cp343-1 (same device)
All versions
siemens-simatic-cp-343-1-lean (same device)
All versions
siemens-simatic-cp-443-1-advanced (same device)
All versions
siemens-simatic-cp-443-1 (same device)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

CVSS

7.5HIGHsiemens
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-119

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