CVE-2026-40355
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.9epss 0.6%
exploitation probability
0.6%top 54% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
MIT · Kerberos 5References
https://cems.fun/2026/04/27/krb5-two-unauthenticated-network-vulnerabilities.htmlhttps://cert-portal.siemens.com/productcert/html/ssa-019113.htmlhttps://cert-portal.siemens.com/productcert/html/ssa-082556.htmlhttps://github.com/krb5/krb5/commit/2e75f0d9362fb979f5fc92829431a590a130929fhttps://web.mit.edu/kerberos/advisories/