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PatchSiren cyber security CVE debrief

CVE-2024-4603 Siemens CVE debrief

CVE-2024-4603 is an availability issue tied to slow DSA parameter/public key validation in OpenSSL. Siemens’ advisory maps the issue to 19 SCALANCE W700 wireless models and recommends upgrading affected devices to firmware V3.0.0 or later.

Vendor
Siemens
Product
SCALANCE WAB762-1 (6GK5762-1AJ00-6AA0)
CVSS
MEDIUM 5.3
CISA KEV
Not listed in stored evidence
Original CVE published
2024-11-12
Original CVE updated
2025-05-06
Advisory published
2024-11-12
Advisory updated
2025-05-06

Who should care

Industrial control and OT teams running Siemens SCALANCE WAB/WAM/WUB/WUM W700 devices, especially administrators responsible for firmware maintenance, device hardening, and exposure of management or certificate-handling workflows.

Technical summary

The underlying issue is that EVP_PKEY_param_check() and EVP_PKEY_public_check() can take excessive time when validating DSA parameters with very large modulus values. If an application feeds untrusted DSA keys or parameters into those checks, an attacker may be able to trigger a denial of service through resource exhaustion. The source notes that OpenSSL’s SSL/TLS implementation is not affected on untrusted DSA keys, while the OpenSSL 3.0 and 3.1 FIPS providers are affected; Siemens lists 19 SCALANCE W700 product variants as affected and provides a firmware fix path.

Defensive priority

Medium

Recommended defensive actions

  • Update affected Siemens SCALANCE W700 devices to V3.0.0 or later.
  • Inventory the 19 affected SCALANCE product variants and confirm current firmware versions.
  • Review any application or integration that performs direct DSA parameter/public key checks on untrusted input.
  • Limit exposure of device management and trust-related interfaces to trusted networks and administrators.
  • Follow CISA ICS recommended practices for segmentation, access control, and monitoring.

Evidence notes

CISA’s CSAF advisory ICSA-25-044-09 was published on 2025-02-11 and revised on 2025-05-06 for typo fixes only. The advisory lists 19 affected Siemens SCALANCE W700 product variants and recommends updating to V3.0.0 or later. The CVE description states the impact is denial of service from slow DSA parameter/public key checks when very large modulus values are processed from untrusted sources. The advisory text also states that OpenSSL’s SSL/TLS implementation is not affected, and that the OpenSSL 3.0 and 3.1 FIPS providers are affected.

Sources and references

Verified primary and authoritative sources

  • CVE-2024-4603 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2024-4603

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

  • CVE-2024-4603 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2024-4603

    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-25-044-09.json

    cisa_csaf

  • Source reference

    Unverified legacy reference

    URL: https://cert-portal.siemens.com/productcert/csaf/ssa-769027.json

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://cert-portal.siemens.com/productcert/html/ssa-769027.html

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/news-events/ics-advisories/icsa-25-044-09

    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/topics/industrial-control-systems

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://us-cert.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.