# CVE-2017-9525: Privilege escalation in n/a

> Local attackers can escalate privileges to root via symlink attacks during the cron package installation or update process.

- **Severity:** Medium 6.7 (`CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 9 Jun 2017
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2017-9525, GHSA-p8jr-r46j-qpx9, UBUNTU-CVE-2017-9525, USN-5259-3

## What is CVE-2017-9525?

CVE-2017-9525 is a medium-severity vulnerability in Debian Debian Linux, published on 9 Jun 2017. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the cron package through 3.0pl1-128 on Debian, and through 3.0pl1-128ubuntu2 on Ubuntu, the postinst maintainer script allows for group-crontab-to-root privilege escalation via symlink attacks against unsafe usage of the chown and chmod programs.

Weakness: CWE-59 (Improper Link Resolution Before File Access)

## Which versions are affected by CVE-2017-9525?

It affects 2 products.


Products: Cron Project Cron, Debian Debian Linux.

## How do I fix CVE-2017-9525?

Apply the vendor's patch.

## Is CVE-2017-9525 being exploited?

There is no known exploitation of CVE-2017-9525 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2019-9704](https://insights.sbomify.com/CVE-2019-9704/): Null dereference in n/a (medium 5.5)
- [CVE-2019-9705](https://insights.sbomify.com/CVE-2019-9705/): Denial of service in n/a (medium 5.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-9525 and fix it if it is affected.

What it is: CVE-2017-9525 is a medium-severity vulnerability in Debian Debian Linux, published on 9 Jun 2017. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2017-9525 in the wild and no public exploit code.

Affected product: Debian Debian 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-2017-9525/ (Markdown: https://insights.sbomify.com/CVE-2017-9525/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-9525
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-9525
- OSV: https://osv.dev/vulnerability/CVE-2017-9525

---
From sbomify Insights: https://insights.sbomify.com/CVE-2017-9525/
Summaries are generated and may contain mistakes; the official description above is the record.