ReviewHigh

CVE-2021-33626

RUGGEDCOM APE1808 - BIOS, SIMATIC Field PG M5

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.

CVSS: 7.8
EPSS: 0.31%
CISA KEV: Not listed
Published: 2021.10.01

PRIORITY ASSESSMENT

Review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.31%

Technical severityCVSS 7.8

Vulnerability overview

Affected product and versions

Product: RUGGEDCOM APE1808 - BIOS, SIMATIC Field PG M5
Affected versions: < V1.0.202N, < V22.01.10, < V26.01.13, < V27.01.09, < V28.01.04, < V21.01.17, < V25.02.12, < V23.01.10, >= 5.3 < 5.34.44, >= 5.2 < 5.25.44, >= 5.1 < 5.16.25, >= 5.4 < 5.42.44, >= 5.3 < 5.35.25, >= 5.2 < 5.26.25, >= 5.4 < 5.43.25
Fixed versions: 5.34.44, 5.25.44, 5.16.25, 5.42.44, 5.35.25, 5.26.25, 5.43.25

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that RUGGEDCOM APE1808 - BIOS, SIMATIC Field PG M5 and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE: CWE-829