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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
NVD MITRE
EPSS Score
0.8%
Top 47.6%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

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

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
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
View detailed technique mapping

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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