CVE-2026-112323: MIT Kerberos 5 kadmind memory exhaustion in AUTH_GSSAPI

CVE-2026-112323 · Severity: high · CVSS 7.5 · Published 2026-11-09

MIT Kerberos 5's administrative daemon (kadmind) processes authentication requests from network clients. An unauthenticated remote attacker can flood the service with repeated failed authentication attempts, causing each to allocate memory that lingers for 15 minutes before being freed. By sending requests faster than memory is reclaimed, an attacker exhausts available memory and crashes the service, disrupting Kerberos authentication for an entire organization.

Technologies: Mit Kerberos 5. Vendors: Mit.

Quick answers

Is CVE-2026-112323 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-112323 being exploited in the wild.
How severe is CVE-2026-112323?
High severity, with a CVSS score of 7.5, published 9 November 2026.
Which products and versions are affected?
Mit Kerberos 5 1.5.2 and later.
Is there a fix for CVE-2026-112323?
No fixed version is recorded yet. Restrict network access to kadmind to trusted hosts, or disable it in favor of the kadmin.local server-side command-line tool for administration operations if possible. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-112323 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-112323?
Check whether you run Mit Kerberos 5 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Restrict network access to kadmind to trusted hosts, or disable it in favor of the kadmin.local server-side command-line tool for administration operations if possible.

Technical details

The AUTH_GSSAPI handler in lib/rpc/svc_auth_gssapi.c allocates per-client state on each authentication request without properly freeing it when the request fails; instead, state persists until a 15-minute timeout expires. An unauthenticated network attacker can send repeated failed AUTH_GSSAPI_INIT requests to exhaust memory in the kadmind process (CWE-772: Missing Release of Resource after Effective Lifetime). This results in denial of service; no code execution or credential compromise occurs.

Affected products

  • MIT Kerberos 5 1.5.2 and later

Timeline

  • 2026-11-09: disclosed

References

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