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CVE-2026-40355 Detail

Description

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 unauthenticated remote attacker can trigger this, causing the process to terminate in parse_nego_message.


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://cems.fun/2026/04/27/krb5-two-unauthenticated-network-vulnerabilities.html CISA-ADP, MITRE
https://github.com/krb5/krb5/commit/2e75f0d9362fb979f5fc92829431a590a130929f MITRE
https://web.mit.edu/kerberos/advisories/ MITRE

Weakness Enumeration

CWE-ID CWE Name Source
CWE-476 NULL Pointer Dereference MITRE  

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-40355
NVD Published Date:
04/28/2026
NVD Last Modified:
04/28/2026
Source:
MITRE