A flaw was found in Samba. The smbd service daemon does not pick up group membership changes when re-authenticating an expired SMB session. This issue can expose file shares until clients disconnect and then connect again.

The remote Ubuntu 25.04 host has packages installed that are affected by a vulnerability as referenced in the USN-7564-1 advisory.

    It was discovered that Samba incorrectly handled certain group membership changes when using Kerberos     authentication. A remote user could possibly use this issue to continue to access resources after being     removed by an administrator.

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Fedora 41 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2025-c9b7df0f0d advisory.

    Update to version 4.21.6


Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Fedora 42 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2025-68d1e02e61 advisory.

    Update to Samba 4.22.2 - Security fix for CVE-2025-0620

Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The version of Samba installed on the remote host is 4.21.x prior to 4.21.6, or 4.22.x prior to 4.22.2. It is, therefore, affected by a security bypass vulnerability. A flaw exists with smbd when using Kerberos authentication with smb, due to using the cached user group permissions when re-authenticating. An authenticated, remote attacker can exploit this, to continue accessing a user group after being removed.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Fedora 43 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2025-a0d44a3ecf advisory.

    Automatic update for samba-4.22.2-1.fc43.

    ##### **Changelog**

    ```
    * Thu Jun  5 2025 Gnther Deschner <gd@samba.org> - 2:4.22.2-1
    - Update to Samba 4.22.2
    - resolves: rhbz#2370468
    - resolves: rhbz#2370455 - Security fix for CVE-2025-0620
    * Wed Jun  4 2025 Python Maint <python-maint@redhat.com> - 2:4.22.1-2
    - Rebuilt for Python 3.14

    ```

Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
238162	Ubuntu 25.04 : Samba vulnerability (USN-7564-1)	Nessus	Ubuntu Local Security Checks	medium
237941	Fedora 41 : samba (2025-c9b7df0f0d)	Nessus	Fedora Local Security Checks	medium
237933	Fedora 42 : samba (2025-68d1e02e61)	Nessus	Fedora Local Security Checks	medium
237907	Samba 4.21.x < 4.21.6 / 4.22.x < 4.22.2 Security Bypass Vulnerability	Nessus	Misc.	high
237874	Fedora 43 : samba (2025-a0d44a3ecf)	Nessus	Fedora Local Security Checks	critical

Detections

Analytics

CVE-2025-0620

medium

Tenable Plugins

medium

medium

medium

high

critical