This page tracks the Ubuntu fix status. The vulnerability itself is described on the main CVE page.
View CVE-2026-104034 →
UBUNTU-CVE-2026-104034
A flaw was found in SSSD. A use-after-free vulnerability exists in the Kerberos Credential Manager (KCM) responder during Kerberos ticket-granting tic...
Original description
The description as published by the source.
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).
Source: OSV.dev (Open Source Vulnerabilities) OSV
Affected packages
Ubuntu:Pro:16.04:LTS
sssd
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Ubuntu:Pro:18.04:LTS
sssd
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Ubuntu:Pro:20.04:LTS
sssd
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Ubuntu:22.04:LTS
sssd
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Ubuntu:24.04:LTS
sssd
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Ubuntu:26.10
sssd
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Ubuntu:26.04:LTS
sssd
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
References
- report ubuntu.com
- report cve.org
- report bugzilla.redhat.com
- report access.redhat.com