- Critical 9.3
- Known exploited (CISA KEV)
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 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 th…
Scores
The facts
- Published
- 5 October 2026
- Last changed
- 19 October 2026
- NVD status
- Analyzed
- Severity
- Critical, CVSS 9.3 out of 10 (version 4.0)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R… - Weakness
- Affects
- atlassian bitbucket data center
- atlassian bitbucket server
- atlassian confluence data center
- atlassian crowd
- atlassian jira data center
- Known exploited
- Yes. CISA added it to the Known Exploited Vulnerabilities catalogue on 15 October 2026.
- EPSS
- No EPSS score in this build.
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