# CVE-2026-21582: Auth bypass in Crowd Data Center

> Unauthenticated attackers can perform actions as another user in Crowd Data Center, requiring an upgrade to mitigate.

- **Severity:** High 8.8 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:H/SI:H/SA: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:** 18 Aug 2026
- **Updated:** 20 Aug 2026
- **Also known as:** GHSA-vxxr-hxj5-58vp

## What is CVE-2026-21582?

CVE-2026-21582 is a high-severity authentication bypass vulnerability in Atlassian Crowd Data Center, published on 18 Aug 2026. 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

This High severity BASM (Broken Authentication & Session Management) vulnerability known as CVE-2026-21582 was introduced in version 7.2.1 of Crowd Data Center.

This BASM (Broken Authentication & Session Management) vulnerability, with a CVSS Score of 8.8, allows an unauthenticated attacker to perform actions as another user.
	
	Atlassian recommends that Crowd Data Center customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions:
		
		Crowd Data Center 7.2: Upgrade to a release greater than or equal to 7.2.2
		
		
	
	See the release notes (https://confluence.atlassian.com/crowd/crowd-release-notes-199094.html). You can download the latest version of Crowd Data Center from the download center (https://www.atlassian.com/software/crowd/download-archive). 
	
	This vulnerability was reported via our Penetration Testing program.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2026-21582?


## How do I fix CVE-2026-21582?

No fix has been published for CVE-2026-21582 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-21582 being exploited?

There is no known exploitation of CVE-2026-21582 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-21582 and fix it if it is affected.

What it is: CVE-2026-21582 is a high-severity authentication bypass vulnerability in Atlassian Crowd Data Center, published on 18 Aug 2026. 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-2026-21582 in the wild and no public exploit code.

Affected product: Atlassian Crowd 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-2026-21582/ (Markdown: https://insights.sbomify.com/CVE-2026-21582/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-21582
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-21582
- OSV: https://osv.dev/vulnerability/CVE-2026-21582

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-21582/
Summaries are generated and may contain mistakes; the official description above is the record.