CVE-2021-27383

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-05-12 · updated 2026-06-17
Weakness: CWE-770

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 server Tight encoder, which could result in a Denial-of-Service condition.

Affected products

Siemens Simatic Hmi Comfort Outdoor Panels 15" Firmware: before 16; before 15.1; 16, 16-update1, 16-update2, 16-update3, 15.1, 15.1-update1 (+4) — fixed in 15.1, 16
Siemens Simatic Hmi Comfort Outdoor Panels 7" Firmware: before 16; before 15.1; 16, 16-update1, 16-update2, 16-update3, 15.1, 15.1-update1 (+4) — fixed in 15.1, 16
Siemens Simatic Hmi Comfort Panels 22" Firmware: before 16; before 15.1; 16, 16-update1, 16-update2, 16-update3, 15.1, 15.1-update1 (+4) — fixed in 15.1, 16
Siemens Simatic Hmi Comfort Panels 4" Firmware: before 16; before 15.1; 16, 16-update1, 16-update2, 16-update3, 15.1, 15.1-update1 (+4) — fixed in 15.1, 16
Siemens Simatic Hmi Ktp Mobile Panels Ktp400F Firmware: before 16; before 15.1; 16, 16-update1, 16-update2, 16-update3, 15.1, 15.1-update1 (+4) — fixed in 15.1, 16
Siemens Simatic Hmi Ktp Mobile Panels Ktp700 Firmware: before 16; before 15.1; 16, 16-update1, 16-update2, 16-update3, 15.1, 15.1-update1 (+4) — fixed in 15.1, 16
Siemens Simatic Hmi Ktp Mobile Panels Ktp700F Firmware: before 16; before 15.1; 16, 16-update1, 16-update2, 16-update3, 15.1, 15.1-update1 (+4) — fixed in 15.1, 16
Siemens Simatic Hmi Ktp Mobile Panels Ktp900 Firmware: before 16; before 15.1; 16, 16-update1, 16-update2, 16-update3, 15.1, 15.1-update1 (+4) — fixed in 15.1, 16
Siemens Simatic Hmi Ktp Mobile Panels Ktp900F Firmware: before 16; before 15.1; 16, 16-update1, 16-update2, 16-update3, 15.1, 15.1-update1 (+4) — fixed in 15.1, 16
Siemens SIMATIC WinCC Runtime Advanced: before 16; before 15.1; 16, 16-update1, 16-update2, 16-update3, 15.1, 15.1-update1 (+4) — fixed in 15.1, 16
Siemens Sinamics Gh150 Firmware: all versions
Siemens Sinamics Gl150 Firmware: all versions
Siemens Sinamics Gm150 Firmware: all versions
Siemens Sinamics Sh150 Firmware: all versions
Siemens Sinamics Sl150 Firmware: all versions
Siemens Sinamics Sm120 Firmware: all versions
Siemens Sinamics Sm150 Firmware: all versions
Siemens Sinamics Sm150I Firmware: all versions

How to fix

Upgrade to a fixed version: Siemens Simatic Hmi Comfort Outdoor Panels 15" Firmware 15.1, 16; Siemens Simatic Hmi Comfort Outdoor Panels 7" Firmware 15.1, 16; Siemens Simatic Hmi Comfort Panels 22" Firmware 15.1, 16; Siemens Simatic Hmi Comfort Panels 4" Firmware 15.1, 16; Siemens Simatic Hmi Ktp Mobile Panels Ktp400F Firmware 15.1, 16; Siemens Simatic Hmi Ktp Mobile Panels Ktp700 Firmware 15.1, 16; Siemens Simatic Hmi Ktp Mobile Panels Ktp700F Firmware 15.1, 16; Siemens Simatic Hmi Ktp Mobile Panels Ktp900 Firmware 15.1, 16; Siemens Simatic Hmi Ktp Mobile Panels Ktp900F Firmware 15.1, 16; Siemens SIMATIC WinCC Runtime Advanced 15.1, 16. Check the vendor advisory for mitigations.

References

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