# CVE-2025-0620: Samba: smbd doesn't pick up group membership changes when re-authenticating an expired smb session

> Samba fails to update group memberships during session re-authentication, allowing unauthorized access to file shares until clients reconnect.

- **Severity:** Medium 4.9 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 6 Jun 2025
- **Updated:** 31 Aug 2026
- **Also known as:** ALPINE-CVE-2025-0620, CLSA-2026-1778859875, DEBIAN-CVE-2025-0620, GHSA-8q8w-8225-6gq4, SUSE-SU-2025:02230-1, USN-7564-1, openSUSE-SU-2025:15296-1

## What is CVE-2025-0620?

CVE-2025-0620 is a medium-severity missing authorization vulnerability in Samba Samba, published on 6 Jun 2025. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

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.

Weakness: CWE-552 (Files or Directories Accessible to External Parties)

## Which versions are affected by CVE-2025-0620?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `samba` | SUSE:Linux Enterprise High Availability Extension 15 SP7 | All versions | 4.21.6+git.402.80f493f530f-150700.3.3.1 |
| `samba` | SUSE:Linux Enterprise Module for Basesystem 15 SP7 | All versions | 4.21.6+git.402.80f493f530f-150700.3.3.1 |
| `samba` | openSUSE:Tumbleweed | All versions | 4.22.2+git.396.c752843dcf4-1.1 |

Products: Samba Samba.

## How do I fix CVE-2025-0620?

Apply the vendor's patch.

## Is CVE-2025-0620 being exploited?

There is no known exploitation of CVE-2025-0620 in the wild and no public exploit code.

## Other vulnerabilities in Samba Samba

- [CVE-2012-1182](https://insights.sbomify.com/CVE-2012-1182/): Integer overflow in n/a (critical 10.0)
- [CVE-2007-2446](https://insights.sbomify.com/CVE-2007-2446/): Memory corruption in n/a (critical 10.0)
- [CVE-2004-0600](https://insights.sbomify.com/CVE-2004-0600/): Memory corruption in n/a (critical 10.0)
- [CVE-1999-0810](https://insights.sbomify.com/CVE-1999-0810/): Denial of service in n/a (critical 10.0)
- [CVE-1999-0182](https://insights.sbomify.com/CVE-1999-0182/): Memory corruption in n/a (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-0620 and fix it if it is affected.

What it is: CVE-2025-0620 is a medium-severity missing authorization vulnerability in Samba Samba, published on 6 Jun 2025. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-0620 in the wild and no public exploit code.

Affected product: Samba Samba. 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-2025-0620/ (Markdown: https://insights.sbomify.com/CVE-2025-0620/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-0620
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-0620
- OSV: https://osv.dev/vulnerability/CVE-2025-0620

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-0620/
Summaries are generated and may contain mistakes; the official description above is the record.