CVE-2026-104048

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.

Statement

This vulnerability is rated as Moderate impact because exploitation requires a non-default trust deployment and an account collision between the local and trusted domains. An authenticated user within a trusted domain can bypass Host-Based Access Control (HBAC) restrictions if their username matches a local Identity Management user explicitly named in an allow rule. The flaw cannot be leveraged remotely by unauthenticated actors, and environments without cross-realm trusts or those utilizing group-based HBAC policies are not exposed.

Mitigation

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score6.88.16.8
Attack VectorNetworkNetworkNetwork
Attack ComplexityHighLowHigh
Privileges RequiredLowLowLow
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityHighHighHigh
Integrity ImpactHighHighHigh
Availability ImpactNoneNoneNone

Vector

Red Hat: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

NVD: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

cve.org: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

Understanding the Weakness (CWE)

Other

Technical Impact: Varies by Context

This can lead to incorrect results and resultant weaknesses. For example, the code might inadvertently compare references to objects, instead of the relevant contents of those objects, causing two "equal" objects to be considered unequal.

Acknowledgements

This issue was discovered by Found by AISLE in partnership with Red Hat.

Frequently Asked Questions

Want to get errata notifications? Sign up here.