# CVE-2017-16857: Race condition in Auto-Unapprove Plugin (for Bitbucket Server)

> Attackers can bypass code review restrictions via race conditions to merge unauthorized code into repositories using the Bitbucket auto-unapprove plugin.

- **Severity:** High 8.5 (`CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H`)
- **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:** 5 Dec 2017
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-wrg5-4633-4gg8

## What is CVE-2017-16857?

CVE-2017-16857 is a high-severity vulnerability in Atlassian Auto-Unapprove Plugin (for Bitbucket Server), published on 5 Dec 2017. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

It is possible to bypass the bitbucket auto-unapprove plugin via minimal brute-force because it is relying on asynchronous events on the back-end. This allows an attacker to merge any code into unsuspecting repositories. This affects all versions of the auto-unapprove plugin, however since the auto-unapprove plugin is not bundled with Bitbucket Server it does not affect any particular version of Bitbucket.

Weakness: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2017-16857?

It affects 1 product.


Products: Atlassian Bitbucket Auto Unapprove Plugin.

## How do I fix CVE-2017-16857?

No fix has been published for CVE-2017-16857 yet. Limit exposure of the affected software until one is available.

## Is CVE-2017-16857 being exploited?

There is no known exploitation of CVE-2017-16857 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-16857 and fix it if it is affected.

What it is: CVE-2017-16857 is a high-severity vulnerability in Atlassian Auto-Unapprove Plugin (for Bitbucket Server), published on 5 Dec 2017. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2017-16857 in the wild and no public exploit code.

Affected product: Atlassian Auto-Unapprove Plugin (for Bitbucket Server). 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-2017-16857/ (Markdown: https://insights.sbomify.com/CVE-2017-16857/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-16857
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-16857
- OSV: https://osv.dev/vulnerability/CVE-2017-16857

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From sbomify Insights: https://insights.sbomify.com/CVE-2017-16857/
Summaries are generated and may contain mistakes; the official description above is the record.