CVE-2021-33627

Published: Feb 3, 2022Updated: Aug 11, 2026 Sources: CVE List NVDCWE-119

8.2HIGH

NVD MITRE

Description

An issue was discovered in Insyde InsydeH2O Kernel 5.0 before 05.09.11, 5.1 before 05.17.11, 5.2 before 05.27.11, 5.3 before 05.36.11, 5.4 before 05.44.11, and 5.5 before 05.52.11 affecting FwBlockServiceSmm. Software SMI services that use the Communicate() function of the EFI_SMM_COMMUNICATION_PROTOCOL do not check whether the address of the buffer is valid, which allows use of SMRAM, MMIO, or OS kernel addresses.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:LAttack Vector

Local

AC:LAttack Complexity

Low

PR:HPrivileges Required

High

UI:NUser Interaction

None

Scope

S:CScope

Changed

Impact

C:HConfidentiality

High

I:HIntegrity

High

A:HAvailability

High

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Weaknesses

CWE-119

Affected Products

siemens

commercial·DEaka siemens ag

simatic field pg m5 firmware

ICS / OT / IoT

simatic field pg m6 firmware

ICS / OT / IoT

simatic ipc127e firmware

ICS / OT / IoT

simatic ipc227g firmware

ICS / OT / IoT

simatic ipc277g firmware

ICS / OT / IoT

simatic ipc327g firmware

ICS / OT / IoT

simatic ipc377g firmware

ICS / OT / IoT

simatic ipc427e firmware

ICS / OT / IoT

insyde

commercial·TWaka insydeh2o

insydeh2oEmbeddedFirmware

Hardware Firmware / bios-uefi

and 7 more affected products View all →

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Initial Access

Privilege Escalation

View detailed technique mapping

References

https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf

cert-portal.siemens.com

https://security.netapp.com/advisory/ntap-20220222-0002/

security.netapp.com

https://www.insyde.com/security-pledge

insyde.com

and 3 more references View all →

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