# CVE-2017-18109: Open redirect in Crowd

> Remote attackers can redirect users to malicious sites via the login resource, facilitating phishing attacks against Atlassian Crowd users.

- **Severity:** Medium 6.1 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 29 Mar 2019
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-3jv4-c99q-p2j6

## What is CVE-2017-18109?

CVE-2017-18109 is a medium-severity vulnerability in Atlassian Crowd, published on 29 Mar 2019. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

The login resource of CrowdId in Atlassian Crowd before version 3.0.2 and from version 3.1.0 before version 3.1.1 allows remote attackers to redirect users to a different website which they may use as part of performing a phishing attack via an open redirect.

Weakness: CWE-601 (URL Redirection to Untrusted Site)

## Which versions are affected by CVE-2017-18109?

It affects 1 product.


Products: Atlassian Crowd.

## How do I fix CVE-2017-18109?

No fix has been published for CVE-2017-18109 yet. Limit exposure of the affected software until one is available.

## Is CVE-2017-18109 being exploited?

There is no known exploitation of CVE-2017-18109 in the wild and no public exploit code.

## Other vulnerabilities in Atlassian Crowd

- [CVE-2019-11580](https://insights.sbomify.com/CVE-2019-11580/): Atlassian Crowd and Crowd Data Center Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2022-43782](https://insights.sbomify.com/CVE-2022-43782/): Auth bypass in Crowd Data Center (critical 9.8)
- [CVE-2016-6496](https://insights.sbomify.com/CVE-2016-6496/): Deserialization in n/a (critical 9.8)
- [CVE-2017-18105](https://insights.sbomify.com/CVE-2017-18105/): Auth bypass in Crowd (high 8.1)
- [CVE-2018-20238](https://insights.sbomify.com/CVE-2018-20238/): Auth bypass in Crowd (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-18109 and fix it if it is affected.

What it is: CVE-2017-18109 is a medium-severity vulnerability in Atlassian Crowd, published on 29 Mar 2019. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2017-18109 in the wild and no public exploit code.

Affected product: Atlassian Crowd. 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-2017-18109/ (Markdown: https://insights.sbomify.com/CVE-2017-18109/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-18109
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-18109
- OSV: https://osv.dev/vulnerability/CVE-2017-18109

---
From sbomify Insights: https://insights.sbomify.com/CVE-2017-18109/
Summaries are generated and may contain mistakes; the official description above is the record.