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PatchSiren cyber security CVE debrief

CVE-2023-37558 CODESYS CVE debrief

CVE-2023-37558 is an authenticated denial-of-service issue affecting multiple CODESYS products and versions as distributed with Festo Automation Suite. A user who has already authenticated can send crafted network communication requests with inconsistent content and cause the CmpAppForce component to read from an invalid address, potentially disrupting availability. The issue is distinct from CVE-2023-37559.

Vendor
CODESYS
Product
FESTO
CVSS
MEDIUM 6.5
CISA KEV
Not listed in stored evidence
Original CVE published
2025-04-10
Original CVE updated
2025-04-10
Advisory published
2025-04-10
Advisory updated
2025-04-10

Who should care

OT and engineering teams running Festo Automation Suite installations that include affected CODESYS components, especially where authenticated users can access the service. Security and operations staff should also care if system availability is important to production or commissioning workflows.

Technical summary

According to the CISA CSAF advisory for ICSA-26-076-01, the flaw occurs after successful authentication and is triggered by specific crafted network communication requests with inconsistent content. The result is an internal invalid-address read in CmpAppForce, which can lead to a denial-of-service condition. The advisory lists affected Festo Automation Suite configurations including versions below 2.8.0.138 and bundled CODESYS Development System components such as 3.0, 3.5.16.10, and 3.5.21.20.

Defensive priority

Medium

Recommended defensive actions

  • Update to the latest patched CODESYS release from the official CODESYS website.
  • Apply Festo Automation Suite updates as released by Festo, including connector updates.
  • Review which systems still bundle or rely on affected CODESYS versions and plan remediation accordingly.
  • Limit authenticated access to affected OT/engineering services to only the users who need it.
  • Monitor vendor security advisories for follow-on fixes or version-specific guidance.

Evidence notes

Primary evidence comes from CISA's CSAF advisory ICSA-26-076-01 for 'CODESYS in Festo Automation Suite' published on 2026-02-26 and republished from Festo on 2026-03-17. The advisory description states that after successful authentication, crafted network communication requests with inconsistent content can cause CmpAppForce to read from an invalid address, leading to denial of service. The source metadata lists affected Festo Automation Suite and CODESYS Development System versions and remediation guidance to install patched CODESYS releases and keep Festo updates current.

Sources and references

Verified primary and authoritative sources

  • CVE-2023-37558 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2023-37558

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

  • CVE-2023-37558 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2023-37558

    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-26-076-01.json

    cisa_csaf

  • Source reference

    Unverified legacy reference

    URL: https://festo.csaf-tp.certvde.com/.well-known/csaf/white/2026/fsa-202601.json

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://certvde.com/en/advisories/vendor/festo/

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.festo.com/psirt

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://certvde.com/en/advisories/VDE-2025-108

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cve.org/CVERecord?id=CVE-2025-2595

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/news-events/ics-advisories/icsa-26-076-01

    Reference

  • Source reference

    Unverified legacy reference

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

    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.