CVE-2026-21589: Atlassian Multiple Products Files or Directories Accessible to External Parties Vulnerability
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.
- Published by source
- 2026-10-15
- First seen by Reality Radar
- 2026-10-20
- Last verified
- 2026-10-20
Affected
- Manufacturer
- Atlassian
- Products
- Multiple Products Atlassian Multiple Products
Whether your exact unit is affected depends on the model, serial number and region in the official notice.
What the official notice says
Risk: Actively exploited in the wild
Remedy / actions:
- 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 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.
Is this affecting you?
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Sources
- CISA Known Exploited Vulnerabilities Tier A · official published 2026-10-15
Evidence ledger
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