All vulnerabilities
CVE-2026-21589

Atlassian Multiple Products Files or Directories Accessible to External Parties Vulnerability

Atlassian Multiple Products
Open in ThreatlineRecord JSON
CVSS
9.3Critical
ExploitationExploited in the wildAdded to KEV 15 Oct 2026CISA KEV
Exploit odds (EPSS)12.7%Chance of exploitation activity in the next 30 days, higher than 96% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed inNone listedNo source names a fixed version. Check the vendor advisory below
Federal deadline18 Oct 2026Remediation due date for US federal agenciesCISA KEV
CISA required actionApply 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 applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines. CISA KEV
Patching is not enoughCISA requires federal agencies to look for signs of compromise on affected systems, not only patch (forensic triage under BOD 26-04). Treat exposed systems as possibly compromised. CISA guidance

What fixes it

No source in this snapshot names a fixed version. The vendor advisories under References are the place to check.

Timeline

  1. 5 Oct 2026, 21:30 UTCPublishedCVE List
  2. 6 Oct 2026, 17:01 UTCExploit code publicwatchTowr Labs
  3. 7 Oct 2026, 12:11 UTCFirst reported exploitedRapid7
  4. 12 Oct 2026, 00:00 UTCWAF rule availableCloudflare WAF
  5. 15 Oct 2026Added to CISA KEVCISA KEV

Protection while you patch 1

WAF and edge providers that shipped rules for this CVE. A rule can block known attack patterns; it does not fix the software, so still upgrade.

Public exploit code and templates 1

  • Scanner templateAtlassian Jira/Confluence/Bitbucket - Pre-Auth Arbitrary File ReadNuclei

Listed so defenders can prioritize. Threatline links to the source and does not host exploit code.

Reports 3

3 outlets mention it. Reports are not confirmation; each links to its source.

Description

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.

Text from CVE List

Affected versions 27

  • Bamboo Data Centeraffected: All other versionsCVE List
  • Bamboo Data Centerunaffected: Patch version 10.2.24 and laterCVE List
  • Bamboo Data Centerunaffected: Patch version 12.1.12 and laterCVE List
  • Bitbucket Data Centeraffected: All other versionsCVE List
  • Bitbucket Data Centerunaffected: Patch version 10.2.8 and laterCVE List
  • Bitbucket Data Centerunaffected: Patch version 10.5.1 and laterCVE List
  • Bitbucket Data Centerunaffected: Patch version 9.4.26 and laterCVE List
  • Confluence Data Centeraffected: All other versionsCVE List
  • Confluence Data Centerunaffected: Patch version 10.2.19 and laterCVE List
  • Confluence Data Centerunaffected: Patch version 9.2.26 and laterCVE List
  • Crowd Data Centeraffected: All other versionsCVE List
  • Crowd Data Centerunaffected: Patch version 7.2.4 and laterCVE List
  • Crowd Data Centerunaffected: Patch version 7.1.7 and laterCVE List
  • Crowd Data Centerunaffected: Patch version 7.0.3 and laterCVE List
  • Crowd Data Centerunaffected: Patch version 6.3.7 and laterCVE List
  • Crucible Data Centeraffected: All other versionsCVE List
  • Crucible Data Centerunaffected: Patch version 4.9.15 and laterCVE List
  • Fisheye Data Centeraffected: All other versionsCVE List
  • Fisheye Data Centerunaffected: Patch version 4.9.15 and laterCVE List
  • Jira Service Management Data Centeraffected: All other versionsCVE List
  • Jira Service Management Data Centerunaffected: Patch version 11.3.12 and laterCVE List
  • Jira Service Management Data Centerunaffected: Patch version 10.3.26 and laterCVE List
  • Jira Service Management Data Centerunaffected: Patch version 5.12.40 and laterCVE List
  • Jira Software Data Centeraffected: All other versionsCVE List
  • Jira Software Data Centerunaffected: Patch version 11.3.12 and laterCVE List
  • Jira Software Data Centerunaffected: Patch version 10.3.26 and laterCVE List
  • Jira Software Data Centerunaffected: Patch version 9.12.40 and laterCVE List

References 12