CVE-2026-40356 (GCVE-0-2026-40356)
Vulnerability from cvelistv5
Published
2026-04-28 00:00
Modified
2026-04-28 13:10
Severity ?
5.9 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-191 - Integer Underflow (Wrap or Wraparound)
Summary
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.
References
Impacted products
Vendor Product Version
MIT Kerberos 5 Version: 1.18   < 1.22.3
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