PatchSiren

PatchSiren cyber security CVE debrief

CVE-2025-31935 Subnet Solutions Inc. CVE debrief

CVE-2025-31935 is a medium-severity denial-of-service issue in Subnet Solutions PowerSYSTEM Center 2020. According to the CISA CSAF advisory published on 2025-04-10, crafted data passed to the API can trigger an exception and disrupt service. Subnet Solutions later revised the advisory on 2025-05-06 for typo fixes only.

Vendor
Subnet Solutions Inc.
Product
PowerSYSTEM Center 2020
CVSS
MEDIUM 6.2
CISA KEV
Not listed in stored evidence
Original CVE published
2025-04-10
Original CVE updated
2025-05-06
Advisory published
2025-04-10
Advisory updated
2025-05-06

Who should care

Operators and administrators of Subnet Solutions Inc. PowerSYSTEM Center 2020 deployments, especially systems at or below version 5.24.x. Industrial control system teams that rely on PSC for notifications or email dispatch should also review the mitigations.

Technical summary

The advisory describes a mishandling of exceptional conditions in PowerSYSTEM Center that can be reached through crafted API input. The result is a denial-of-service condition. The supplied CVSS vector is CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H, indicating high availability impact and a local attack condition in the published scoring.

Defensive priority

Medium priority. Patch promptly if PowerSYSTEM Center is exposed in operational environments, or apply the vendor mitigations immediately where updating is not feasible.

Recommended defensive actions

  • Update PowerSYSTEM Center to the latest vendor-recommended release.
  • For PSC 2020 deployments, apply PSC 2020 Update 25.
  • For PSC 2024 deployments, apply the current PSC 2024 release.
  • If updating is not possible, disable Notification Service, Email Dispatch Service, or the outgoing email server in Notifications/Settings.
  • Configure the PowerSYSTEM Center DCS network firewall to allow connections only to an approved and authorized email server.
  • Limit and manage administrator access to the PowerSYSTEM Center DCS operating system.
  • Monitor user activity records to confirm acceptable use of the application.
  • Contact Subnet Solutions support directly for update assistance if needed.

Evidence notes

This debrief is based on the CISA CSAF advisory for ICSA-25-100-08 / CVE-2025-31935 and the embedded remediation guidance. The affected scope in the supplied corpus is Subnet Solutions Inc. PowerSYSTEM Center 2020: <=5.24.x. The advisory revision history shows the 2025-05-06 update was for typo fixes only. No KEV listing, ransomware linkage, or exploitation reporting is included in the supplied sources.

Sources and references

Verified primary and authoritative sources

  • CVE-2025-31935 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2025-31935

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

  • CVE-2025-31935 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2025-31935

    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/2025/icsa-25-100-08.json

    cisa_csaf

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/news-events/ics-advisories/icsa-25-100-08

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/uscert/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/sites/default/files/publications/Cybersecurity_Best_Practices_for_Industrial_Control_Systems.pdf

    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/uscert/sites/default/files/publications/emailscams0905.pdf

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/uscert/ncas/tips/ST04-014

    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.