CVE-2026-21589

h3. Summary 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.   h3. Context This vulnerability allows an unauthenticated remote attacker to access specific files within the web application root directory in affected versions. h3. Details: * 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, 7.1.1, 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.

CVSS

9.3

EPSS

—

CISA KEV

Not listed

Exploitation

none

Public exploits

None seen

State

PUBLISHED

Coverage

• Help Net Security◇Specialist. Specialist publisher: established trade press, or expert analysis with a track record2 hours ago

  Atlassian urges immediate patching of critical Data Center file access vulnerability (CVE-2026-21589)

  Attackers who know where to look can read files from Atlassian Data Center installations without logging in, the company has warned. About CVE-2026-21589 CVE-2026-21589, a critical arbitrary file access vulnerability with a 9.3 CVSS score, affects all versions of Bitbucket Data Center, Confluence…

  ↗helpnetsecurity.com/2026/10/06/atlassian-data-c…(opens the publisher's site in a new tab)

What we observed