CVE-2025-11840 Siemens CVE debrief

Who should care

Organizations operating the affected Siemens SIMATIC S7-1500 CPU family products, especially environments where the additional GNU/Linux subsystem or interactive shell is available. Asset owners, OT/ICS administrators, and maintenance teams should review exposure even though the issue is locally exploitable and rated LOW, because public exploit availability increases risk for trusted-user or adjacent-system abuse.

Technical summary

The supplied source corpus identifies an out-of-bounds read in the vfinfo function within ldmisc.c, associated with GNU Binutils 2.45. The CVSS vector is AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L, indicating a local attack requiring limited privileges and causing limited availability impact. Siemens’ advisory context links the issue to the SIMATIC S7-1500 CPU 1518-4/1518F-4 PN/DP MFP variants and the SIPLUS variant, and the remediation text emphasizes restricting shell access and only running trusted applications. The same source set also notes that no fix is currently available for the listed products, despite the CVE description referring to patch 16357.

Defensive priority

Medium for affected Siemens OT assets with local shell or trusted-user access; lower for environments where the GNU/Linux subsystem is not exposed. Priority should increase if untrusted operators, contractors, or shared administrative access exist, or if the affected CPUs are reachable by users who could execute local code.

Recommended defensive actions

• Limit access to the interactive shell of the additional GNU/Linux subsystem to trusted personnel only.
• Only build and run applications from trusted sources.
• Review which of the five affected Siemens CPU variants are deployed in your environment and confirm whether the GNU/Linux subsystem is enabled or reachable.
• Apply vendor guidance from Siemens/CISA advisories as soon as a fix or updated mitigation becomes available.
• Monitor for unusual local activity on affected engineering or runtime systems, especially where privileged user access is shared.

Evidence notes

The core vulnerability description comes from the supplied CVE text: a weakness in GNU Binutils 2.45, specifically vfinfo in ldmisc.c, resulting in an out-of-bounds read and requiring local execution. The Siemens CSAF source maps CVE-2025-11840 to five SIMATIC S7-1500 CPU family products and includes mitigation-only guidance, including restricting shell access and trusting application sources. The source corpus also states that no fix is currently available for the listed products, while the CVE description mentions patch 16357; this debrief preserves both statements without asserting an unverified deployment path for the patch.

Official resources