Siemens SIMATIC S7 PLC Web Server
This CISA advisory details multiple vulnerabilities discovered within Siemens SIMATIC S7 PLCs, specifically within their web servers. These vulnerabilities, identified as CVE-2026-25786 through CVE-2026-25789, allow for potential cross-site scripting attacks. Siemens has released updated versions of affected products and recommends immediate updates to mitigate the risk.
Siemens has identified and disclosed a series of vulnerabilities impacting several of its SIMATIC S7 PLC models. These vulnerabilities reside within the web server component of the PLCs, presenting a potential entry point for attackers. The identified CVEs (CVE-2026-25786, CVE-2026-25787, CVE-2026-25789) allow for the execution of cross-site scripting (XSS) attacks, potentially enabling an attacker to inject malicious scripts into the PLC's web interface. Siemens is providing updated software versions to address these issues, and strongly recommends immediate deployment of these updates. Furthermore, Siemens is preparing additional fix versions and recommends specific countermeasures for products where immediate fixes are unavailable.