# CVE-2025-23395: Local root exploit via `logfile_reopen()` in screen 5.0.0 with setuid-root bit set

> Unprivileged users can escalate to root by exploiting a privilege dropping failure in GNU Screen when setuid-root is enabled.

- **Severity:** High 7.3 (`CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 26 May 2025
- **Updated:** 27 May 2025
- **Also known as:** ALPINE-CVE-2025-23395, BELL-CVE-2025-23395, GHSA-84g7-x869-xfgv

## What is CVE-2025-23395?

CVE-2025-23395 is a high-severity vulnerability, published on 26 May 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Screen 5.0.0 when it runs with setuid-root privileges does not drop privileges while operating on a user supplied path. This allows unprivileged users to create files in arbitrary locations with `root` ownership, the invoking user's (real) group ownership and file mode 0644. All data written to the Screen PTY will be logged into this file, allowing to escalate to root privileges

Weakness: CWE-271 (Privilege Dropping / Lowering Errors)

## Which versions are affected by CVE-2025-23395?


## How do I fix CVE-2025-23395?

Apply the vendor's patch.

## Is CVE-2025-23395 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-23395 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-23395 and fix it if it is affected.

What it is: CVE-2025-23395 is a high-severity vulnerability, published on 26 May 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-23395 exists.

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-2025-23395/ (Markdown: https://insights.sbomify.com/CVE-2025-23395/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-23395
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-23395
- OSV: https://osv.dev/vulnerability/CVE-2025-23395

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-23395/
Summaries are generated and may contain mistakes; the official description above is the record.