CVE-2021-44695

Severity: medium (CVSS 4.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-12-13 · updated 2026-06-17
Weakness: CWE-1286

Description

Affected devices don't process correctly certain special crafted packets sent to port 102/tcp, which could allow an attacker to cause a denial of service in the device.

Affected products

Siemens Simatic Et 200 Sp Open Controller Cpu 1515Sp Pc Firmware: all versions
Siemens Simatic S7-1200 Cpu 1211C Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 1212C Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 1212Fc Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 1214 Fc Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 1214C Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 1214Fc Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 1215 Fc Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 1215C Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 1215Fc Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 1217C Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 12 1211C Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 12 1212C Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 12 1212Fc Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 12 1214C Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 12 1214Fc Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 12 1215C Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 12 1215Fc Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1200 Cpu 12 1217C Firmware: before 4.6.0 — fixed in 4.6.0
Siemens Simatic S7-1500 Cpu 1507S F Firmware: before 3.0.1 — fixed in 3.0.1
Siemens Simatic S7-1500 Cpu 1507S Firmware: before 3.0.1 — fixed in 3.0.1
Siemens Simatic S7-1500 Cpu 1508S F Firmware: before 3.0.1 — fixed in 3.0.1
Siemens Simatic S7-1500 Cpu 1508S Firmware: before 3.0.1 — fixed in 3.0.1
Siemens Simatic S7-1500 Cpu 1510Sp-1 Firmware: before 3.0.1 — fixed in 3.0.1
Siemens Simatic S7-1500 Cpu 1510Sp Firmware: before 3.0.1 — fixed in 3.0.1
Siemens Simatic S7-1500 Cpu 1511-1 Firmware: before 3.0.1 — fixed in 3.0.1
Siemens Simatic S7-1500 Cpu 1511-1 Pn Firmware: before 3.0.1 — fixed in 3.0.1
Siemens Simatic S7-1500 Cpu 1511C-1 Firmware: before 3.0.1 — fixed in 3.0.1
Siemens Simatic S7-1500 Cpu 1511C Firmware: before 3.0.1 — fixed in 3.0.1
Siemens Simatic S7-1500 Cpu 1511F-1 Firmware: before 3.0.1 — fixed in 3.0.1

How to fix

Upgrade to a fixed version: Siemens Simatic S7-1200 Cpu 1211C Firmware 4.6.0; Siemens Simatic S7-1200 Cpu 1212C Firmware 4.6.0; Siemens Simatic S7-1200 Cpu 1212Fc Firmware 4.6.0; Siemens Simatic S7-1200 Cpu 1214 Fc Firmware 4.6.0; Siemens Simatic S7-1200 Cpu 1214C Firmware 4.6.0; Siemens Simatic S7-1200 Cpu 1214Fc Firmware 4.6.0; Siemens Simatic S7-1200 Cpu 1215 Fc Firmware 4.6.0; Siemens Simatic S7-1200 Cpu 1215C Firmware 4.6.0; Siemens Simatic S7-1200 Cpu 1215Fc Firmware 4.6.0; Siemens Simatic S7-1200 Cpu 1217C Firmware 4.6.0; Siemens Simatic S7-1200 Cpu 12 1211C Firmware 4.6.0; Siemens Simatic S7-1200 Cpu 12 1212C Firmware 4.6.0. Check the vendor advisory for mitigations.

References

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