What is CVE-2026-40355?

CVE-2026-40355 is a medium-severity vulnerability in Mit Kerberos 5, classified under NULL Pointer Dereference. CVSS score: 5.9/10. Published 2026-04-28.

How severe is CVE-2026-40355?

Medium severity. CVSS v3 base score is 5.9 out of 10.

NULL pointer dereference in Mit Kerberos 5

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 unauthenticated remote attacker can trigge…

EPSS: 0.001 (28.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Mit Kerberos 5 — versions 1.18

Weakness classification (CWE)

CWE-476 — NULL Pointer Dereference

References

cve@mitre.org
cve@mitre.org
cve@mitre.org

Frequently asked questions

What is CVE-2026-40355?: CVE-2026-40355 is a medium-severity vulnerability in Mit Kerberos 5, classified under NULL Pointer Dereference. CVSS score: 5.9/10. Published 2026-04-28.
How severe is CVE-2026-40355?: Medium severity. CVSS v3 base score is 5.9 out of 10.