CVE-2021-33626

HIGH

InsydeH2O 5.3-5.34.44 - Arbitrary Code Execution via SWSMI Handler Buffer Validation

Title source: llm
STIX 2.1

Description

A vulnerability exists in SMM (System Management Mode) branch that registers a SWSMI handler that does not sufficiently check or validate the allocated buffer pointer(QWORD values for CommBuffer). This can be used by an attacker to corrupt data in SMRAM memory and even lead to arbitrary code execution.

References (5)

Core 5
Core References
Vendor Advisory x_refsource_misc
https://www.insyde.com/security-pledge
Vendor Advisory x_refsource_misc
https://www.insyde.com/security-pledge/SA-2021001
Third Party Advisory x_refsource_confirm
https://security.netapp.com/advisory/ntap-20220216-0006/
Third Party Advisory x_refsource_confirm
https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf
Third Party Advisory, US Government Resource
https://www.kb.cert.org/vuls/id/796611

Scores

CVSS v3 7.8
EPSS 0.0030
EPSS Percentile 21.1%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Details

CWE
CWE-829
Status published
Products (17)
insyde/insydeh2o 5.3 - 5.34.44
siemens/ruggedcom_apr1808_firmware
siemens/simatic_field_pg_m5_firmware
siemens/simatic_field_pg_m6_firmware
siemens/simatic_ipc127e_firmware
siemens/simatic_ipc227g_firmware
siemens/simatic_ipc277g_firmware
siemens/simatic_ipc327g_firmware
siemens/simatic_ipc377g_firmware
siemens/simatic_ipc427e_firmware
... and 7 more
Published Oct 01, 2021
Tracked Since Feb 18, 2026