dbcve.org
CrowdApplication · Atlassian

CVE-2023-22521

HIGH · 8.8 CVSS v3.1 Published 2023-11-21
Fix available
A fix is available. Upgrade to 5.1.6 or later.
See remediation →
94/100
Remediation priority · Urgent
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
This High severity RCE (Remote Code Execution) vulnerability was introduced in version 3.4.6 of Crowd Data Center and Server. This RCE (Remote Code Execution) vulnerability, with a CVSS Score of 8.0, allows an authenticated attacker to execute arbitrary code which has high impact to confidentiality, high impact to integrity, high impact to availability, and requires no user interaction. Atlassian recommends that Crowd Data Center and Server 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 and Server 3.4: Upgrade to a release greater than or equal to 5.1.6 Crowd Data Center and Server 5.2: Upgrade to a release greater than or equal to 5.2.1 See the release notes ([https://confluence.atlassian.com/crowd/crowd-release-notes-199094.html]). You can download the latest version of Crowd Data Center and Server from the download center ([https://www.atlassian.com/software/crowd/download-archive]). This vulnerability was discovered by m1sn0w and reported via our Bug Bounty program

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

Authenticated RCE vulnerability in Atlassian Crowd Data Center and Server introduced in version 3.4.6. An authenticated attacker can execute arbitrary code with high impact to confidentiality, integrity, and availability, requiring no user interaction.

MitigationUpgrade Atlassian Crowd to version 5.1.6 or later (for 3.4.x branches) or version 5.2.1 or later (for 5.2.x branches), or migrate to the latest available version.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
CrowdApplication
Affected:>= 3.4.0, < 5.1.6= 5.2.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify if Atlassian Crowd is installed
    Look for Crowd installation directories (commonly at /opt/atlassian/crowd, /var/atlassian/crowd, or C:\atlassian\crowd on Windows). Check for crowd-webapp.war or crowd directory in application servers.
    Affected if Atlassian Crowd is present on the system
  2. Determine the installed Crowd version
    Check the CROWD-INF/VERSION file in the Crowd home directory, or look at the admin interface under 'Crowd > Administration > Overview' which displays the version number.
    Affected if Version is >= 3.4.0 and < 5.1.6, or equals 5.2.0
  3. Verify Crowd is network-accessible
    Check if the Crowd application port (default 8095 or configured port) is listening on an accessible network interface. Use 'netstat -an | grep 8095' or equivalent to verify the listening address.
    Affected if Crowd is accessible from network (not localhost-only) and version is in affected range
  4. Confirm user authentication is enabled
    Review Crowd's user directory configuration in the admin panel under 'User Directories' to confirm external or internal users can authenticate.
    Affected if Any user directory is configured and the version is in the affected range

You are affected if Atlassian Crowd Data Center or Server is installed with a version >= 3.4.0 and < 5.1.6, or exactly version 5.2.0, and the application is accessible to authenticate attackers.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 5.1.6 or later
Fixed in 5.1.6
Interim mitigation

Upgrade Atlassian Crowd to version 5.1.6 or later (for 3.4.x branches) or version 5.2.1 or later (for 5.2.x branches), or migrate to the latest available version.

Recommended fix High confidence

Crowd 5.1.6+ (for 3.4.x branches) or Crowd 5.2.1+ (for 5.2.0)

  1. 1. Back up your Crowd Data Center or Server instance, including database and configuration files
  2. 2. Download the fixed version of Crowd from the Atlassian download center (5.1.6 or later for 3.4.x branches; 5.2.1 or later for 5.2.0)
  3. 3. Stop the Crowd service
  4. 4. Install or upgrade to the downloaded fixed version following Atlassian's upgrade documentation
  5. 5. Start the Crowd service and verify the installation
  6. 6. Validate that the vulnerability is resolved

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Crowd Scoped from the published advisory
  • Consultation4.0 h
  • Implementation12.0 h
  • Testing8.0 h
  • Review / QA3.0 h
27.0 hours of engineering $4,700
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $7,520.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2023-22521 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2023-22521 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data