# CVE-2026-112321: MIT Kerberos memory exhaustion in AUTH_GSSAPI handler

Source: https://junglewise.ai/threats/cve-2026-112321-the-auth-gssapi-handler-in-lib-rpc-svc-auth-gssapi-c-in-mit  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-09. Updated: 2026-11-09  
License: CC BY 4.0 with a link back

CVE-2026-112321 · Severity: high · CVSS 7.5 · Published 2026-11-09

MIT Kerberos 5's administrative authentication handler (kadmind) fails to properly release memory when processing certain malformed authentication requests. An attacker can repeatedly send these crafted requests from the network to exhaust system memory and cause a denial of service, affecting systems that expose Kerberos administrative services to untrusted networks.

Technologies: [Mit Kerberos 5](https://junglewise.ai/threats/technologies/kerberos-5). Vendors: [Mit](https://junglewise.ai/threats/vendors/mit).

## Quick answers

**Is CVE-2026-112321 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-112321 being exploited in the wild.

**How severe is CVE-2026-112321?** High severity, with a CVSS score of 7.5, published 9 November 2026.

**Which products and versions are affected?** MIT Kerberos 5.

**Is there a fix for CVE-2026-112321?** No fixed version is recorded yet. Restrict network access to kadmind to trusted hosts only, or disable kadmind in favor of kadmin.local server-side command line tool for administration 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-2026-112321 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-112321?** Check whether you run Mit Kerberos 5. 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 only, or disable kadmind in favor of kadmin.local server-side command line tool for administration if possible.

## Technical details

The AUTH_GSSAPI_INIT handler in lib/rpc/svc_auth_gssapi.c does not free decoded arguments on specific error paths (CWE-772), allowing remote unauthenticated attackers to trigger memory leaks. The vulnerability is reachable via network-based RPC authentication requests that fail validation, causing memory exhaustion in kadmind without requiring valid Kerberos credentials.

## Affected products

- MIT Kerberos 5

## Timeline

- 2026-11-09: disclosed

## References

- [https://access.redhat.com/downloads/content/package-browser/](https://access.redhat.com/downloads/content/package-browser/)
- [https://access.redhat.com/security/cve/CVE-2026-112321](https://access.redhat.com/security/cve/CVE-2026-112321)

## Related threats

- [MIT Kerberos 5 denial of service in ASN.1 SEQUENCE OF decoding](https://junglewise.ai/threats/cve-2026-119079-decode-sequence-of-in-lib-krb5-asn-1-asn1-encode-c-in-mit)
- [MIT Kerberos 5 kadmind memory exhaustion in AUTH_GSSAPI](https://junglewise.ai/threats/cve-2026-112323-the-auth-gssapi-handler-in-lib-rpc-svc-auth-gssapi-c-in-mit)
- [MIT Kerberos 5 denial of service in kadmind AUTH_GSSAPI cleanup](https://junglewise.ai/threats/cve-2026-112322-clean-client-in-lib-rpc-svc-auth-gssapi-c-in-mit-kerberos-5-aka)
- [MIT Kerberos 5 memory exhaustion via GSS-RPC authentication context leak](https://junglewise.ai/threats/cve-2026-112320-the-gss-rpc-transport-layer-in-mit-kerberos-5-aka-krb5-1-4-and)
- [MIT Kerberos 5 GSS-RPC unbounded memory allocation in kadmind](https://junglewise.ai/threats/cve-2026-112319-the-gss-rpc-layer-in-mit-kerberos-5-aka-krb5-does-not-enforce)