CVE-2026-40355

In MIT Kerberos 5 (aka krb5) before 1.22.3, there is a NULL pointer dereference if an application calls gss_accept_sec_context() on a system with a NegoEx mechanism registered in /etc/gss/mech. An ...

Published: Apr 28, 2026Updated: Jul 14, 2026 Sources: CVE List NVD csafCWE-476

5.9MEDIUM

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:HAttack Complexity

High

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-476

Affected Products

MIT

oss-project·USaka mit krb5, mit kerberos

Kerberos 5On-prem

Operating Systems

and 1 more affected products View all →

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Impact

Initial Access

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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 478 more references View all →

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