Krb5: mit krb5 kadmind unauthenticated memory leak dos via gss-rpc auth flavor switching
Summary
| CVE | CVE-2026-112320 |
|---|---|
| State | PUBLISHED |
| Assigner | redhat |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-11-09 19:16:40 UTC |
| Updated | 2026-11-09 19:16:41 UTC |
| Description | The GSS-RPC transport layer in MIT Kerberos 5 (aka krb5) 1.4 and later does not release the previous authentication context when a client switches from an RPCSEC_GSS or AUTH_GSSAPI flavor to a non-GSS flavor on the same TCP connection. This allows remote attackers to cause a denial of service (memory exhaustion in kadmind) by repeatedly establishing and abandoning GSS authentication contexts. |
Risk And Classification
Primary CVSS: v3.1 7.5 HIGH from [email protected]
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Problem Types: CWE-772 | CWE-772 Missing Release of Resource after Effective Lifetime
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Primary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | CVSS | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Red Hat | Red Hat Enterprise Linux 10 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 6 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 7 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 9 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Hardened Images | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| access.redhat.com/security/cve/CVE-2026-112320 | [email protected] | access.redhat.com | |
| bugzilla.redhat.com/show_bug.cgi | [email protected] | bugzilla.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: This issue was discovered by Found by AISLE in partnership with Red Hat. (en)
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-05-18T03:32:25.000Z | Reported to Red Hat. |
| CNA | 2026-11-09T15:00:00.000Z | Made public. |
Workarounds
CNA: Restrict network access to kadmind to trusted hosts, or disable it in favor of kadmin.local server-side command line tool for administration operations if possible.
There are currently no legacy QID mappings associated with this CVE.