Critical ICSA-26-134-15 3 CVEs

Siemens SIMATIC S7 PLC Web Server

Published May 12, 2026 · Updated May 14, 2026 · Revision 2

Vendor: Siemens Product: SIMATIC Drive Controller CPU 1504D TF (6ES7615-4DF10-0AB0) Product: SIMATIC Drive Controller CPU 1507D TF (6ES7615-7DF10-0AB0) Product: SIMATIC ET 200SP CPU 1510SP F-1 PN (6ES7510-1SJ00-0AB0) Product: SIMATIC ET 200SP CPU 1510SP F-1 PN (6ES7510-1SJ01-0AB0) Product: SIMATIC ET 200SP CPU 1510SP F-1 PN (6ES7510-1SK03-0AB0) Product: SIMATIC ET 200SP CPU 1510SP-1 PN (6ES7510-1DJ00-0AB0) Product: SIMATIC ET 200SP CPU 1510SP-1 PN (6ES7510-1DJ01-0AB0) Product: SIMATIC ET 200SP CPU 1510SP-1 PN (6ES7510-1DK03-0AB0) Product: SIMATIC ET 200SP CPU 1512SP F-1 PN (6ES7512-1SK00-0AB0) Product: SIMATIC ET 200SP CPU 1512SP F-1 PN (6ES7512-1SK01-0AB0) Product: SIMATIC ET 200SP CPU 1512SP F-1 PN (6ES7512-1SM03-0AB0) Product: SIMATIC ET 200SP CPU 1512SP-1 PN (6ES7512-1DK00-0AB0) Product: SIMATIC ET 200SP CPU 1512SP-1 PN (6ES7512-1DK01-0AB0) Product: SIMATIC ET 200SP CPU 1512SP-1 PN (6ES7512-1DM03-0AB0) Product: SIMATIC ET 200SP CPU 1514SP F-2 PN (6ES7514-2SN03-0AB0) Product: SIMATIC ET 200SP CPU 1514SP-2 PN (6ES7514-2DN03-0AB0) Product: SIMATIC ET 200SP CPU 1514SPT F-2 PN (6ES7514-2WN03-0AB0) Product: SIMATIC ET 200SP CPU 1514SPT-2 PN (6ES7514-2VN03-0AB0) Product: SIMATIC ET 200SP Open Controller CPU 1515SP PC (incl. SIPLUS variants) Product: SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants) V2 CPUs Product: SIMATIC ET 200SP Open Controller CPU 1515SP PC3 V4 CPUs Product: SIMATIC S7-1500 CPU 1511-1 PN (6ES7511-1AK00-0AB0) Product: SIMATIC S7-1500 CPU 1511-1 PN (6ES7511-1AK01-0AB0) Product: SIMATIC S7-1500 CPU 1511-1 PN (6ES7511-1AK02-0AB0) Product: SIMATIC S7-1500 CPU 1511-1 PN (6ES7511-1AL03-0AB0) Product: SIMATIC S7-1500 CPU 1511C-1 PN (6ES7511-1CK00-0AB0) Product: SIMATIC S7-1500 CPU 1511C-1 PN (6ES7511-1CK01-0AB0) Product: SIMATIC S7-1500 CPU 1511C-1 PN (6ES7511-1CL03-0AB0) Product: SIMATIC S7-1500 CPU 1511F-1 PN (6ES7511-1FK00-0AB0) +120 more

Summary

SIMATIC S7 PLCs contain multiple vulnerabilities in the web server that could allow an attacker to perform cross-site scripting attacks.

Siemens has released new versions for several affected products and recommends to update to the latest versions. Siemens is preparing further fix versions and recommends specific countermeasures for products where fixes are not, or not yet available.

Vulnerabilities 3

Critical 9.1

CVE-2026-25786

Affected devices do not properly validate and sanitize PLC/station name rendered on the "communication" parameters page…

Siemens SIMATIC S7-1500 CPU 1515T-2 PN SIMATIC S7-1500 CPU 1512C-1 PN SIMATIC S7-1500 CPU 1516-3 PN/DP ICS / OT

May 12, 2026
Critical 9.1

CVE-2026-25787

Affected devices do not properly validate and sanitize Technology Object (TO) name rendered on the "Motion Control Diag…

Siemens SIMATIC S7-1500 CPU 1511F-1 PN SIMATIC S7-1500 CPU 1515F-2 PN SIMATIC Drive Controller CPU 1507D TF ICS / OT

May 12, 2026
High 7.1

CVE-2026-25789

Affected devices do not properly validate and sanitize filenames on the Firmware Update page. This could allow a remote…

Siemens SIMATIC S7-1500 CPU 1516F-3 PN/DP SIMATIC S7-1500 CPU 1511C-1 PN SIMATIC S7-1500 CPU 1515-2 PN ICS / OT

May 12, 2026

Revision history

2026-05-14 #2
Initial CISA Republication of Siemens ProductCERT SSA-688146 advisory
2026-05-12 #1
Publication Date

References

SSA-688146: Multiple Cross-Site Scripting Vulnerabilities in SIMATIC S7 PLCs Web Server - HTML Version
https://cert-portal.siemens.com/productcert/html/ssa-688146.html
ICS Advisory ICSA-26-134-15 - Web Version
https://www.cisa.gov/news-events/ics-advisories/icsa-26-134-15
Recommended Practices
https://www.cisa.gov/news-events/ics-alerts/ics-alert-10-301-01
Recommended Practices
https://www.cisa.gov/resources-tools/resources/ics-recommended-practices
Recommended Practices
https://www.cisa.gov/topics/industrial-control-systems
Recommended Practices
https://www.cisa.gov/sites/default/files/recommended_practices/NCCIC_ICS-CERT_Defense_in_Depth_2016_S508C.pdf
Recommended Practices
https://www.cisa.gov/sites/default/files/publications/Cybersecurity_Best_Practices_for_Industrial_Control_Systems.pdf
Recommended Practices
https://www.cisa.gov/news-events/news/targeted-cyber-intrusion-detection-and-mitigation-strategies-update-b