CVE-2026-104048 Sssd: sssd: authorization bypass via cross-domain username collision in hbac evaluation
Authenticated users in trusted domains can bypass HBAC rules via username collisions, gaining unauthorized access to protected hosts in SSSD environments.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-104048?
CVE-2026-104048 is a medium-severity authentication bypass vulnerability in Redhat Enterprise Linux, published on 6 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A flaw was found in SSSD. In trust-enabled identity management environments, SSSD evaluates Host-Based Access Control (HBAC) rules by stripping domain qualifiers and comparing only short usernames. An authenticated user in a trusted domain who shares the same username as an authorized local account can bypass access policies and gain unauthorized access to protected services or hosts.
Weakness: CWE-1025
Which versions are affected by CVE-2026-104048?
It affects 3 products.
Products include Fedoraproject Sssd, Redhat Enterprise Linux, Redhat Openshift Container Platform.
How do I fix CVE-2026-104048?
No fix has been published for CVE-2026-104048 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-104048 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-104048 exists.
Other vulnerabilities in Redhat Enterprise Linux
Sources
Also known as DEBIAN-CVE-2026-104048, GHSA-474r-m56w-5qgh, UBUNTU-CVE-2026-104048.