What is CVE-2023-43505?

CVE-2023-43505 is a critical-severity vulnerability in Siemens Comos, classified under Improper Access Control. CVSS score: 9.6/10. Published 2023-11-14.

How severe is CVE-2023-43505?

Critical severity. CVSS v3 base score is 9.6 out of 10.

Vulnerability in Siemens Comos

CVE-2023-43505

A vulnerability has been identified in COMOS (All versions). The affected application lacks proper access controls in SMB shares. This could allow an attacker to access files that the user should not have access to.

Published 2023-11-14 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.6 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.006 (47.5th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 47.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Siemens Comos — versions All versions

Weakness classification (CWE)

CWE-284 — Improper Access Control

References

cert-portal.siemens.com/productcert/pdf/ssa-137900.pdf (Vendor Advisory)

Frequently asked questions

What is CVE-2023-43505?: CVE-2023-43505 is a critical-severity vulnerability in Siemens Comos, classified under Improper Access Control. CVSS score: 9.6/10. Published 2023-11-14.
How severe is CVE-2023-43505?: Critical severity. CVSS v3 base score is 9.6 out of 10.