CVE-2026-40356
MEDIUM EPSS 36.6%
Published Apr 28, 20262mo ago · Modified Jun 17, 20261w ago
5.9 CVSS 3.1
Published Apr 28, 2026 2mo ago
Last Modified Jun 17, 2026 1w ago
Description
In MIT Kerberos 5 (aka krb5) before 1.22.3, there is an integer underflow and resultant out-of-bounds read 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, possibly causing the process to terminate in parse_message.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector Network
Attack Complexity High
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High
Threat Intelligence
EPSS Exploit Probability
36.6% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-191
References 3
- cems.fun https://cems.fun/2026/04/27/krb5-two-unauthenticated-network-vulnerabilities.html
- github.com https://github.com/krb5/krb5/commit/2e75f0d9362fb979f5fc92829431a590a130929f
- web.mit.edu https://web.mit.edu/kerberos/advisories/
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.