Unauthenticated Arbitrary File Access in Atlassian Data Center (v4.6.0+)
CVE-2026-21589 Published on October 5, 2026

This is a vulnerability in Bitbucket Data Center, Confluence Data Center, Jira Service Management Data Center, Jira Software Data Center, Bamboo Data Center. Crowd Data Center, Crucible and Fisheye. This Arbitrary File Access vulnerability allows an unauthenticated attacker to access specific files within the web application root directory in affected versions. Exploitation requires prior knowledge of the target file's exact name and path; this vulnerability does not allow attackers to enumerate or list directory contents. In some configurations, there may be some sensitive files that make this highly severe. This vulnerability allows an unauthenticated remote attacker to access specific files within the web application root directory in affected versions. The vulnerability must be addressed for affected versions of: -- Bitbucket Data Center, introduced in version >= 4.6.0, fix versions: 9.4.26, 10.2.8, 10.5.1 -- Confluence Data Center, introduced in version >= 5.10.0, fix versions 9.2.26, 10.2.19 -- Crowd Data Center, introduced in version >= 2.11.0, fix versions 6.3.7, 7.0.3, 7.1.7, 7.2.4 -- Jira Software Data Center, introduced in version >= 7.1.0, fix versions 9.12.40, 10.3.26, 11.3.12 -- Jira Service Management Data Center, introduced in version >= 3.1.0, fix versions 5.12.40, 10.3.26, 11.3.12 -- Bamboo Data Center >= 7.0.1, fix versions 10.2.24, 12.1.12 -- Crucible, fix versions 4.9.15 -- Fisheye, fix version 4.9.15 -- Exploitation requires prior knowledge of the target file's exact name and path. The vulnerability does not include the capability to enumerate or list directory contents.

NVD

Under Active Exploitation

This vulnerability is under active exploitation.

Known Exploited Vulnerability

This Atlassian Multiple Products Files or Directories Accessible to External Parties Vulnerability is part of CISA's list of Known Exploited Vulnerabilities. Multiple Atlassian products (Bitbucket Data Center ,Confluence Data Center, Jira Service Management Data Center, Jira Software Data Center, Bamboo Data Center, Crowd Data Center, Crucible and Fisheye) contain a files or directories accessible to external parties vulnerability which could allow an unauthenticated attacker to access specific files within the web application root directory in affected versions.

The following remediation steps are recommended / required by October 18, 2026: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicab

Vulnerability Analysis

Exploitation:
ACTIVE
Automatable:
NO
Technical Impact:
TOTAL

Weakness Type

Files or Directories Accessible to External Parties

The product makes files or directories accessible to unauthorized actors, even though they should not be. Web servers, FTP servers, and similar servers may store a set of files underneath a "root" directory that is accessible to the server's users. Applications may store sensitive files underneath this root without also using access control to limit which users may request those files, if any. Alternately, an application might package multiple files or directories into an archive file (e.g., ZIP or tar), but the application might not exclude sensitive files that are underneath those directories.


Products Associated with CVE-2026-21589

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Atlassian Bamboo
Atlassian Bitbucket Data Center
Atlassian Bitbucket
Atlassian Confluence
Atlassian Crowd
Atlassian Crucible
Atlassian Fisheye
Atlassian Jira
Atlassian Jira Software Data Center

Affected Versions

Atlassian Bamboo Data Center: Atlassian Bitbucket Data Center: Atlassian Confluence Data Center: Atlassian Crowd Data Center: Atlassian Crucible Data Center: Atlassian Fisheye Data Center: Atlassian Jira Service Management Data Center: Atlassian Jira Software Data Center: