CVE-2026-27135

nghttp2 Denial of service: Assertion failure due to the missing state validation

Published: Mar 18, 2026Updated: Jul 15, 2026 Sources: CVE List NVD csafCWE-617

7.5HIGH

Description

Multiple vulnerabilities have been identified in the additional GNU/Linux subsystem of the firmware version V3.1.6 for the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP (incl. SIPLUS variant). Siemens is preparing fix versions and recommends specific countermeasures for products where fixes are not, or not yet available.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-617

Affected Products

nghttp2

oss-projectaka ngtcp2

nghttp2Library

OSS Libraries / generic-library

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Impact

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References

https://cert-portal.siemens.com/productcert/csaf/ssa-019113.json

cert-portal.siemens.com

https://cert-portal.siemens.com/productcert/html/ssa-019113.html

cert-portal.siemens.com

https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/OT/white/2026/icsa-26-209-04.json

raw.githubusercontent.com

and 528 more references View all →

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