Servers and applications
CVE-2026-21589
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…
Actively exploited: CISA added it to its Known Exploited Vulnerabilities catalog on 15 Oct 2026.
- Severity
- Critical 9.3
- Published
- 5 Oct 2026
- Last changed
- 19 Oct 2026
- Added to UpHeron
- 21 Oct 2026
- Fixed in
- 9.2.26, 10.2.19
- Sources
- NVD
Affected software
| Software | Affected versions |
|---|---|
ConfluenceServers and applications · cpe:a:atlassian:confluence_data_center |
|
Known exploited
- CISA name
- Atlassian Multiple Products Files or Directories Accessible to External Parties Vulnerability
- Required action
- 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…
- Due for US agencies
- 18 Oct 2026
- Used in ransomware
- Not known