A vulnerability has been identified in LOGO!

published 2020-12-14 5 y ago modified 2026-06-17 4 mo ago also EUVD-2020-17924

cvss: 7.7; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 24%
public exploits: 0; none known

A vulnerability has been identified in LOGO! 8 BM (incl. SIPLUS variants) (All versions < V8.3), LOGO! Soft Comfort (All versions < V8.3). The LOGO! program files generated and used by the affected components offer the possibility to save user-defined functions (UDF) in a password protected way. This protection is implemented in the software that displays the information. An attacker could reverse engineer the UDFs directly from stored program files.

Patch / fix

fixed in 1

siemens logo!_8_bm_firmware 8.3

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-20-343-10 updated 2020-12-08 cvss 7.7

Siemens LOGO! 8 BM

Siemens LOGO! 8 BM (incl.'SIPLUS variants) <V8.3
affected: fixed in V8.3, mitigation support.industry.siemens.com
Siemens LOGO! Soft Comfort <V8.3
affected: fixed in V8.3, mitigation support.industry.siemens.com

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

Exploit prediction

0.32% chance of exploitation in the next 30 days, higher than 24% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.1	7.7	CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
NVD	2.0	3.6	AV:L/AC:L/Au:N/C:P/I:P/A:N

Affected products

Siemens LOGO! 8 BM (incl. SIPLUS variants)
Siemens LOGO! Soft Comfort

Classification

Weakness

CWE-321 Use of Hard-coded Cryptographic Key

References

cert-portal.siemens.com /productcert/pdf/ssa-480824.pdf
vendor-advisory

Sources

CVE List CVE-2020-25234
NVD CVE-2020-25234

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary