# 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.

- **Severity:** Medium 6.8 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 6 Oct 2026
- **Updated:** 7 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-104048, GHSA-474r-m56w-5qgh, UBUNTU-CVE-2026-104048

## 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 (Comparison Using Wrong Factors)

## Which versions are affected by CVE-2026-104048?

It affects 3 products.


Products: 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.

## 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

- [CVE-2022-4254](https://insights.sbomify.com/CVE-2022-4254/): Other in SSSD (high 8.8)
- [CVE-2012-3462](https://insights.sbomify.com/CVE-2012-3462/): Auth bypass in sssd (high 8.8)
- [CVE-2015-5292](https://insights.sbomify.com/CVE-2015-5292/): Denial of service in n/a (medium 6.8)
- [CVE-2026-12610](https://insights.sbomify.com/CVE-2026-12610/): Sssd: use-after-free crash in sssd' 'sssd_pam' process (medium 6.4)
- [CVE-2026-104046](https://insights.sbomify.com/CVE-2026-104046/): Sssd: sssd: denial of service via incomplete identity provider authentication requests (medium 6.2)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-104048 and fix it if it is affected.

What it is: 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.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-104048 exists.

Affected product: Redhat Enterprise Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-104048/ (Markdown: https://insights.sbomify.com/CVE-2026-104048/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-104048
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-104048
- OSV: https://osv.dev/vulnerability/CVE-2026-104048

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-104048/
Summaries are generated and may contain mistakes; the official description above is the record.