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CVE-2024-27316 Apache Software Foundation CVE debrief

CVE-2024-27316 is a HIGH severity (CVSS 7.5) denial-of-service vulnerability affecting Siemens SINEC NMS. The issue stems from the nghttp2 HTTP/2 library's handling of incoming headers that exceed configured limits. When excessive headers are received, nghttp2 temporarily buffers them to generate an HTTP 413 (Payload Too Large) response. A malicious client can exploit this behavior by continuously sending headers without stopping, causing unbounded memory growth and eventual memory exhaustion on the target system. The vulnerability is network-exploitable with low attack complexity, requires no privileges or user interaction, and results in high availability impact. Siemens has released a vendor fix in SINEC NMS V3.0 SP1 and later versions.

Vendor
Apache Software Foundation
Product
SINEC NMS
CVSS
HIGH 7.5
CISA KEV
Not listed in stored evidence
Original CVE published
2024-11-12
Original CVE updated
2024-11-12
Advisory published
2024-11-12
Advisory updated
2024-11-12

Who should care

Organizations operating Siemens SINEC NMS for industrial network management, critical infrastructure operators with OT/ICS environments, security teams responsible for HTTP/2 service hardening, and asset owners following CISA ICS security guidance

Technical summary

The vulnerability exists in how nghttp2 handles HTTP/2 incoming headers that exceed configured limits. Rather than immediately rejecting excessive headers, nghttp2 buffers them temporarily to construct an informative HTTP 413 response. This buffering mechanism becomes a resource exhaustion vector when a client deliberately continues sending headers without terminating the stream. The unbounded memory growth leads to denial of service conditions on affected Siemens SINEC NMS deployments. The issue is classified as CWE-770 (Allocation of Resources Without Limits or Throttling).

Defensive priority

HIGH

Recommended defensive actions

  • Upgrade Siemens SINEC NMS to V3.0 SP1 or later version to address the nghttp2 memory exhaustion vulnerability
  • Monitor for abnormal HTTP/2 traffic patterns indicating potential exploitation attempts
  • Apply network segmentation controls to limit exposure of SINEC NMS management interfaces
  • Review and implement CISA ICS recommended practices for defense-in-depth strategies

Evidence notes

The vulnerability description and remediation guidance are derived from CISA CSAF advisory ICSA-24-319-04, which references Siemens security advisory SSA-331112. The CVSS vector confirms network attack vector, low complexity, no privileges required, and high availability impact.

Sources and references

Verified primary and authoritative sources

  • CVE-2024-27316 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2024-27316

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

  • CVE-2024-27316 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2024-27316

    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/2024/icsa-24-319-04.json

    cisa_csaf

  • Source reference

    Unverified legacy reference

    URL: https://cert-portal.siemens.com/productcert/csaf/ssa-331112.json

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://cert-portal.siemens.com/productcert/html/ssa-331112.html

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/news-events/ics-advisories/icsa-24-319-04

    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.