Vulnerability · Published Oct 6, 2026 · Assigned by redhat
CVE-2026-104034Sssd: sssd: denial of service via use-after-free in kcm ticket renewal
Medium 4.7
In plain English
A medium-severity security flaw in Red Hat Enterprise Linux 10 from Red Hat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 0% of all known vulnerabilities).
Official description
A flaw was found in SSSD. A use-after-free vulnerability exists in the Kerberos Credential Manager (KCM) responder during Kerberos ticket-granting ticket (TGT) renewal, where a deferred callback accesses memory that has already been released. An authenticated local user with a renewable Kerberos ticket can trigger this issue on systems configured with KCM renewal, causing the KCM responder service to crash and resulting in a Denial of Service (DoS).
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | sssd | no fix listed | DEBIAN-CVE-2026-104034 |
| Debian:13 | sssd | no fix listed | DEBIAN-CVE-2026-104034 |
| Ubuntu:22.04:LTS | sssd | no fix listed | UBUNTU-CVE-2026-104034 |
| Ubuntu:24.04:LTS | sssd | no fix listed | UBUNTU-CVE-2026-104034 |
| Ubuntu:26.04:LTS | sssd | no fix listed | UBUNTU-CVE-2026-104034 |
| Ubuntu:26.10 | sssd | no fix listed | UBUNTU-CVE-2026-104034 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | see references |
| Red Hat | Red Hat Enterprise Linux 6 | see references |
| Red Hat | Red Hat Enterprise Linux 7 | see references |
| Red Hat | Red Hat Enterprise Linux 8 | see references |
| Red Hat | Red Hat Enterprise Linux 9 | see references |
| Red Hat | Red Hat OpenShift Container Platform 4 | see references |
| Red Hat | Red Hat OpenShift Container Platform 4 | see references |
| Red Hat | Red Hat OpenShift Container Platform 5 | see references |
Weakness: CWE-825 · Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
References
- https://access.redhat.com/security/cve/CVE-2026-104034 vdb-entry, x_refsource_REDHAT
- RHBZ#2479178 issue-tracking, x_refsource_REDHAT