# CVE-2020-4026: Missing authorization in Crucible

> Remote attackers can enumerate all linked applications, including hidden ones, due to incorrect authorization checks in Atlassian Navigator Links.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N`)
- **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:** 2 Jun 2020
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-5x3c-hcgh-mgxq

## What is CVE-2020-4026?

CVE-2020-4026 is a medium-severity missing authorization vulnerability in Atlassian Crucible, published on 2 Jun 2020. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

The CustomAppsRestResource list resource in Atlassian Navigator Links before version 3.3.23, from version 4.0.0 before version 4.3.7, from version 5.0.0 before 5.0.1, and from version 5.1.0 before 5.1.1 allows remote attackers to enumerate all linked applications, including those that are restricted or otherwise hidden, through an incorrect authorization check.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2020-4026?

It affects 1 product.


Products: Atlassian Navigator Links.

## How do I fix CVE-2020-4026?

No fix has been published for CVE-2020-4026 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-4026 being exploited?

There is no known exploitation of CVE-2020-4026 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-4026 and fix it if it is affected.

What it is: CVE-2020-4026 is a medium-severity missing authorization vulnerability in Atlassian Crucible, published on 2 Jun 2020. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-4026 in the wild and no public exploit code.

Affected product: Atlassian Crucible. 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-2020-4026/ (Markdown: https://insights.sbomify.com/CVE-2020-4026/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-4026
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-4026
- OSV: https://osv.dev/vulnerability/CVE-2020-4026

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-4026/
Summaries are generated and may contain mistakes; the official description above is the record.