Siemens SIMATIC S7-1500 CPU devices before 1.8.3 allow remote attackers to bypass a replay protection mechanism via packets on TCP port 102.

published 2016-02-08 10 y ago modified 2026-06-17 4 mo ago also EUVD-2016-3285

cvss: 5.3; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 2.9%; EPSS 2.9% chance of exploitation in 30 days, percentile 87%
public exploits: 0; none known

Vendor advisories

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

cisa ICSA-16-040-02 updated 2025-06-05 cvss 3.7

Siemens SIMATIC S7-1500 CPU Vulnerabilities

Siemens SIMATIC S7-1500 CPU family <1.8.3
affected: mitigation “Siemens security advisory, SSA-253230, is available at the following URL (https://www.siemens.com/cert/advisories)” support.industry.siemens.com

From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf

Exploit prediction

2.92% chance of exploitation in the next 30 days, higher than 87% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.0	5.3	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:P/A:N

Classification

Weakness

CWE-20 Improper Input Validation

References

siemens.com /cert/pool/cert/siemens_security_advisory_ssa-253230.pdf
vendor-advisory
securitytracker.com /id/1034954
vdb-entry, third-party-advisory
securityfocus.com /bid/83110
vdb-entry, third-party-advisory
ics-cert.us-cert.gov /advisories/ICSA-16-040-02
third-party-advisory, us-government-resource
cert-portal.siemens.com /productcert/pdf/ssa-253230.pdf

Sources

CVE List CVE-2016-2201
NVD CVE-2016-2201

Fencer Intel 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