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CVE-2021-25660

HIGH

7.5

CVSS Score

Published: May 12, 2021 at 01:18 PM UTC

Updated: June 17, 2026 at 03:42 AM UTC

21 products affected across 1 vendorSIMATIC WinCC Runtime AdvancedSIMATIC HMI Ktp Mobile Panels KTP700F FirmwareSIMATIC HMI Ktp Mobile Panels KTP400F Firmware

Using SIMATIC HMI Comfort Outdoor Panels V15 7\" & 15\" (incl. SIPLUS variants) by Siemens?

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Severity

HIGH7.5

Exploit prediction

EPSS 1.0%

SSVC

No known exploit

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). SmartVNC has an out-of-bounds memory access vulnerability that could be triggered on the server side when sending data from the client, which could result in a Denial-of-Service condition.

Affected

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

SIMATIC HMI Comfort Outdoor Panels 15 " Firmware · Siemens

95%

v < 15.1v < 1615.1 15.1 update1 15.1 update2 15.1 update3 15.1 update4 15.1 update5 16 16 update1 16 update2 16 update3

Affected range stops below 15.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 16, so it looks safe — our inference, not a vendor statement

siemens-simatic-hmi-comfort-outdoor-panels-15 (same device)

SIMATIC HMI Comfort Outdoor Panels 7 " Firmware · Siemens

95%

v < 15.1v < 1615.1 15.1 update1 15.1 update2 15.1 update3 15.1 update4 15.1 update5 16 16 update1 16 update2 16 update3

Affected range stops below 15.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 16, so it looks safe — our inference, not a vendor statement

siemens-simatic-hmi-comfort-outdoor-panels-7 (same device)

SIMATIC HMI Comfort Panels 22 " Firmware · Siemens

95%

v < 15.1v < 1615.1 15.1 update1 15.1 update2 15.1 update3 15.1 update4 15.1 update5 16 16 update1 16 update2 16 update3

Affected range stops below 15.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 16, so it looks safe — our inference, not a vendor statement

siemens-simatic-hmi-comfort-panels-22 (same device)

SIMATIC HMI Comfort Panels 4 " Firmware · Siemens

95%

v < 15.1v < 1615.1 15.1 update1 15.1 update2 15.1 update3 15.1 update4 15.1 update5 16 16 update1 16 update2 16 update3

Affected range stops below 15.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 16, so it looks safe — our inference, not a vendor statement

siemens-simatic-hmi-comfort-panels-4 (same device)

SIMATIC HMI Ktp Mobile Panels KTP400F Firmware · Siemens

95%

v < 15.1v < 1615.1 15.1 update1 15.1 update2 15.1 update3 15.1 update4 15.1 update5 16 16 update1 16 update2 16 update3

Affected range stops below 15.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 16, so it looks safe — our inference, not a vendor statement

siemens-simatic-hmi-ktp-mobile-panels-ktp400f (same device)

SIMATIC HMI Ktp Mobile Panels KTP700 Firmware · Siemens

95%

v < 15.1v < 1615.1 15.1 update1 15.1 update2 15.1 update3 15.1 update4 15.1 update5 16 16 update1 16 update2 16 update3

Affected range stops below 15.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 16, so it looks safe — our inference, not a vendor statement

siemens-simatic-hmi-ktp-mobile-panels-ktp700 (same device)

SIMATIC HMI Ktp Mobile Panels KTP700F Firmware · Siemens

95%

v < 15.1v < 1615.1 15.1 update1 15.1 update2 15.1 update3 15.1 update4 15.1 update5 16 16 update1 16 update2 16 update3

Affected range stops below 15.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 16, so it looks safe — our inference, not a vendor statement

siemens-simatic-hmi-ktp-mobile-panels-ktp700f (same device)

SIMATIC HMI Ktp Mobile Panels KTP900 Firmware · Siemens

95%

v < 15.1v < 1615.1 15.1 update1 15.1 update2 15.1 update3 15.1 update4 15.1 update5 16 16 update1 16 update2 16 update3

Affected range stops below 15.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 16, so it looks safe — our inference, not a vendor statement

siemens-simatic-hmi-ktp-mobile-panels-ktp900 (same device)

SIMATIC HMI Ktp Mobile Panels KTP900F Firmware · Siemens

95%

v < 15.1v < 1615.1 15.1 update1 15.1 update2 15.1 update3 15.1 update4 15.1 update5 16 16 update1 16 update2 16 update3

Affected range stops below 15.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 16, so it looks safe — our inference, not a vendor statement

siemens-simatic-hmi-ktp-mobile-panels-ktp900f (same device)

SIMATIC WinCC Runtime Advanced · Siemens

95%

v < 15.1v < 1615.1 15.1 update1 15.1 update2 15.1 update3 15.1 update4 15.1 update5 16 16 update1 16 update2 16 update3 All versions < V15.1 Update 6 All versions < V16 Update 4

Affected range stops below 15.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 16, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

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

Patch and advisory references

https://cert-portal.siemens.com/productcert/pdf/ssa-538778.pdf

References (1)

x_refsource_MISCx_refsource_CONFIRMPatchVendor Advisory

Source: [email protected]

https://cert-portal.siemens.com/productcert/pdf/ssa-538778.pdf

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHCISA-ADP

Attack Vector: NETWORK
Complexity: LOW
Privileges: NONE
User Interaction: NONE
Scope: UNCHANGED
Confidentiality: NONE
Integrity: NONE
Availability: HIGH

Vector?

Quick Info

StatusMODIFIED

CWE

CWE-788CWE-119

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