CVE-2026-40355

Published: Apr 28, 2026Modified: Jul 14, 2026

7.5

Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploitability: 3.9 / Impact: 3.6

Source: NVD

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.

Affected (1)

Products: Mit: Kerberos 5

1 product

Configuration A

1 vulnerable

Vulnerable Software	Affected Versions
Mit Kerberos 5	From 1.18.0 to 1.22.2

Related CWEs

NULL Pointer Dereference

The product dereferences a pointer that it expects to be valid but is NULL.

References (6)

https://cems.fun/2026/04/27/krb5-two-unauthenticated-network-vulnerabilities.html

Source: cve@mitre.org

ExploitPatchThird Party Advisory

https://github.com/krb5/krb5/commit/2e75f0d9362fb979f5fc92829431a590a130929f

Source: cve@mitre.org

Patch

https://web.mit.edu/kerberos/advisories/

Source: cve@mitre.org

Vendor Advisory

https://cems.fun/2026/04/27/krb5-two-unauthenticated-network-vulnerabilities.html

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

ExploitPatchThird Party Advisory

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

Source: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e

https://cert-portal.siemens.com/productcert/html/ssa-082556.html

Source: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e

Timeline

No history available yet.