# CVE-2021-26072: Server-side request forgery in Confluence Data Center

> Remote attackers can manipulate internal network resources via blind SSRF in the WidgetConnector plugin, requiring an upgrade to Confluence Server or Data Center.

- **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:** 1 Apr 2021
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-889g-gr2g-424w

## What is CVE-2021-26072?

CVE-2021-26072 is a medium-severity server-side request forgery vulnerability in Atlassian Confluence Data Center, published on 1 Apr 2021. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

The WidgetConnector plugin in Confluence Server and Confluence Data Center before version 5.8.6 allowed remote attackers to manipulate the content of internal network resources via a blind Server-Side Request Forgery (SSRF) vulnerability.

Weakness: CWE-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2021-26072?

It affects 2 products.


Products: Atlassian Confluence Data Center, Atlassian Confluence Server.

## How do I fix CVE-2021-26072?

No fix has been published for CVE-2021-26072 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-26072 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-26072 exists.

Public exploit code:

- Atlassian Confluence < 5.8.6 - Server-Side Request Forgery (nuclei): http/cves/2021/CVE-2021-26072.yaml

## Other vulnerabilities in Atlassian Confluence Data Center

- [CVE-2023-22527](https://insights.sbomify.com/CVE-2023-22527/): Atlassian Confluence Data Center and Server Template Injection (critical 10.0, exploited in the wild)
- [CVE-2023-22518](https://insights.sbomify.com/CVE-2023-22518/): Atlassian Confluence Data Center and Server Improper Authorization (critical 10.0, exploited in the wild)
- [CVE-2023-22515](https://insights.sbomify.com/CVE-2023-22515/): Atlassian Confluence Data Center and Server Broken Access Control (critical 10.0, exploited in the wild)
- [CVE-2022-26134](https://insights.sbomify.com/CVE-2022-26134/): Atlassian Confluence Server and Data Center Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2021-26084](https://insights.sbomify.com/CVE-2021-26084/): Atlassian Confluence Server and Data Center Object-Graph Navigation Language (OGNL) Injection (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-26072 and fix it if it is affected.

What it is: CVE-2021-26072 is a medium-severity server-side request forgery vulnerability in Atlassian Confluence Data Center, published on 1 Apr 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-26072 exists.

Affected product: Atlassian Confluence Data Center. 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-2021-26072/ (Markdown: https://insights.sbomify.com/CVE-2021-26072/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-26072
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-26072
- OSV: https://osv.dev/vulnerability/CVE-2021-26072

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-26072/
Summaries are generated and may contain mistakes; the official description above is the record.