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CVE-2025-40830 Siemens CVE debrief

CVE-2025-40830 affects Siemens SINEC Security Monitor and stems from missing authorization checks in the ssmctl-client file_transfer feature. According to the advisory text, an authenticated local attacker could read or write arbitrary files on the server or sensor. Siemens recommends updating to V4.10.0 or later.

Vendor
Siemens
Product
SINEC Security Monitor
CVSS
MEDIUM 6.7
CISA KEV
Not listed in stored evidence
Original CVE published
2025-12-09
Original CVE updated
2026-01-14
Advisory published
2025-12-09
Advisory updated
2026-01-14

Who should care

Siemens SINEC Security Monitor administrators, OT/ICS operators, and teams responsible for servers or sensors that expose ssmctl-client functionality or allow local authenticated access.

Technical summary

The source advisory describes improper authorization checks in the file_transfer feature of the ssmctl-client command. Impact is arbitrary file read/write on the server or sensor. The provided CVSS vector is CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H, while the narrative description characterizes the attacker as authenticated and low-privileged locally; both should be treated as source details, not reconciled assumptions.

Defensive priority

Medium, but treat as time-sensitive on any exposed or production SINEC Security Monitor deployment because file read/write access can affect confidentiality, integrity, and availability.

Recommended defensive actions

  • Upgrade Siemens SINEC Security Monitor to V4.10.0 or later as recommended by the vendor.
  • Inventory affected server and sensor deployments and confirm which systems use the ssmctl-client file_transfer feature.
  • Review local accounts and privilege boundaries on affected hosts; limit access to only trusted administrators.
  • Monitor for unexpected file changes or access on servers and sensors, especially where sensitive configurations or data are stored.
  • After patching, validate backups, configuration integrity, and operational behavior on the affected systems.

Evidence notes

Source item: CISA CSAF advisory ICSA-26-015-06 republished Siemens ProductCERT advisory SSA-882673, with initial publication on 2025-12-09 and republication on 2026-01-14. The advisory text states that the application lacks proper authorization checks for the file_transfer feature in ssmctl-client and that this could allow an authenticated, lowly privileged local attacker to read or write any file on the server or sensor. The supplied CVSS vector is CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H, which differs from the prose description on privilege level and should be interpreted carefully.

Sources and references

Verified primary and authoritative sources

  • CVE-2025-40830 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2025-40830

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2025-40830 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2025-40830

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Source item URL

    Unverified legacy reference

    URL: https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/OT/white/2026/icsa-26-015-06.json

    cisa_csaf

  • Source reference

    Unverified legacy reference

    URL: https://cert-portal.siemens.com/productcert/csaf/ssa-882673.json

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://cert-portal.siemens.com/productcert/html/ssa-882673.html

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/news-events/ics-advisories/icsa-26-015-06

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/news-events/ics-alerts/ics-alert-10-301-01

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/resources-tools/resources/ics-recommended-practices

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/topics/industrial-control-systems

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/sites/default/files/recommended_practices/NCCIC_ICS-CERT_Defense_in_Depth_2016_S508C.pdf

    Reference

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.