PatchSiren cyber security CVE debrief

CVE-2024-56643 Siemens CVE debrief

A memory leak vulnerability in the Linux kernel's Datagram Congestion Control Protocol (DCCP) implementation affects Siemens industrial networking products. The flaw occurs in dccp_feat_change_recv where memory allocated for a new SP feature value is not freed if dccp_feat_push_confirm() fails, potentially leading to resource exhaustion. The vulnerability requires local access with low privileges and has a medium severity CVSS 3.1 score of 5.5. Siemens has released updates to address this issue in affected RUGGEDCOM and SCALANCE product families.

Vendor: Siemens
Product: RUGGEDCOM RST2428P (6GK6242-6PA00)
CVSS: MEDIUM 5.5
CISA KEV: Not listed in stored evidence
Original CVE published: 2025-08-12
Original CVE updated: 2026-02-25
Advisory published: 2025-08-12
Advisory updated: 2026-02-25

Who should care

Organizations operating Siemens RUGGEDCOM RST2428P, SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500, or SCALANCE XCM-/XRM-/XCH-/XRH-300 family devices in industrial control system environments should prioritize patching. System administrators responsible for OT/ICS network infrastructure and security teams monitoring industrial networks for availability risks should assess exposure.

Technical summary

The vulnerability exists in the dccp_feat_change_recv function within the Linux kernel's DCCP protocol implementation. When processing feature negotiation, memory is allocated for a new SP (Server/Client Preference) feature value. If the subsequent dccp_feat_push_confirm() call fails, this allocated memory is not properly freed, resulting in a memory leak. Repeated exploitation could lead to resource exhaustion and denial of service conditions. The attack requires local access with low privileges, no user interaction, and affects availability only (no confidentiality or integrity impact per CVSS vector).

Defensive priority

medium

Recommended defensive actions

Apply vendor-provided updates to V3.2 or later for RUGGEDCOM RST2428P and SCALANCE XCM-/XRM-/XCH-/XRH-300 family devices
For SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family, consult Siemens ProductCERT advisory SSA-355557 for specific configuration guidance
Implement network segmentation to limit exposure of affected industrial control systems
Monitor for anomalous resource consumption patterns that may indicate exploitation attempts
Follow CISA ICS recommended practices for defense-in-depth strategies

Evidence notes

CVE published 2025-08-12; CISA advisory ICSA-25-226-07 published same date. Siemens ProductCERT advisory SSA-355557 referenced as authoritative source. Advisory modified 2026-02-25 with republication based on updated Siemens guidance.

Sources and references

Verified primary and authoritative sources

CVE-2024-56643 CVE Program record
Publisher, destination, and source semantics verified

URL: https://www.cve.org/CVERecord?id=CVE-2024-56643

CVE Program - Official CVE Program record with source-provided CVE metadata.
CVE-2024-56643 NVD vulnerability detail
Publisher, destination, and source semantics verified

URL: https://nvd.nist.gov/vuln/detail/CVE-2024-56643

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-25-226-07.json

cisa_csaf
Source reference
Unverified legacy reference

URL: https://cert-portal.siemens.com/productcert/csaf/ssa-355557.json

Reference
Source reference
Unverified legacy reference

URL: https://cert-portal.siemens.com/productcert/html/ssa-355557.html

Reference
Source reference
Unverified legacy reference

URL: https://www.cisa.gov/news-events/ics-advisories/icsa-25-226-07

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.