CRITICAL · CVSS 9.3
ACTIVELY EXPLOITED
PATCH AVAILABLE
CVE-2026-21589: Atlassian Multiple Products Files or Directories Accessible to External Parties Vulnerability
| Vendor | Atlassian |
|---|---|
| Product | Multiple Products |
| CVSS score | 9.3 · CVSS 4.0 · CRITICALCVSS: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:X/V:X/RE:X/U:X |
| EPSS | 99.7% (percentile 100) |
| Actively exploited | Yes |
| Added to CISA KEV | 15 Oct 2026 |
| CISA federal deadline | 18 Oct 2026 |
| Weakness (CWE) | CWE-552 |
| NVD published | 5 Oct 2026 |
| NVD last modified | 29 Oct 2026 |
| NVD status | Analyzed |
Affected versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Atlassian Bamboo | from 7.0.1 before 10.2.24 | 10.2.24 |
| Atlassian Bamboo | from 11.0.0 before 12.1.12 | 12.1.12 |
| Atlassian Bitbucket Data Center | from 9.5.0 before 10.2.8 | 10.2.8 |
| Atlassian Bitbucket Data Center | from 10.3.0 before 10.5.1 | 10.5.1 |
| Atlassian Bitbucket Data Center | from 7.17.0 before 9.4.26 | 9.4.26 |
| Atlassian Bitbucket Server | from 4.6.0 up to 8.14.6 | – |
| Atlassian Confluence Data Center | from 9.3.0 before 10.2.19 | 10.2.19 |
| Atlassian Confluence Data Center | from 5.10.0 before 9.2.26 | 9.2.26 |
| Atlassian Crowd | from 2.11.0 before 6.3.7 | 6.3.7 |
| Atlassian Crowd | from 7.0.0 before 7.0.3 | 7.0.3 |
| Atlassian Crowd | from 7.1.0 before 7.1.7 | 7.1.7 |
| Atlassian Crowd | from 7.2.0 before 7.2.4 | 7.2.4 |
| Atlassian Crucible | before 4.9.15 | 4.9.15 |
| Atlassian Fisheye | before 4.9.15 | 4.9.15 |
| Atlassian Jira Data Center | from 9.13.0 before 10.3.26 | 10.3.26 |
| Atlassian Jira Data Center | from 10.4.0 before 11.3.12 | 11.3.12 |
| Atlassian Jira Data Center | from 7.1.0 before 9.12.40 | 9.12.40 |
| Atlassian Jira Service Desk | from 3.1.0 up to 4.13.27 | – |
| Atlassian Jira Service Management | from 5.13.0 before 10.3.26 | 10.3.26 |
| Atlassian Jira Service Management | from 10.4.0 before 11.3.12 | 11.3.12 |
+1 more
Required action (CISA's text)
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.
Description (NVD)
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. This vulnerability allows an unauthenticated remote attacker to access specific files within the web application root directory in affected versions. 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, 7.1.7, 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.
SOURCES
- NVDNVD entry for CVE-2026-21589
- CISA KEVCISA Known Exploited Vulnerabilities catalog
- VENDORjira.atlassian.com/browse/BAM-26567
- VENDORjira.atlassian.com/browse/BSERV-20604
- VENDORjira.atlassian.com/browse/CONFSERVER-104488
- VENDORjira.atlassian.com/browse/CRUC-8741
- VENDORjira.atlassian.com/browse/CWD-6610
- VENDORjira.atlassian.com/browse/FE-7583
- VENDORjira.atlassian.com/browse/JRASERVER-79546
- VENDORjira.atlassian.com/browse/JSDSERVER-16809
Other Atlassian flaws
- CVE-2021-26086: Atlassian Jira Server and Data Center Path Traversal Vulnerability
- CVE-2023-22527: Atlassian Confluence Data Center and Server Template Injection Vulnerability
- CVE-2023-22518: Atlassian Confluence Data Center and Server Improper Authorization Vulnerability
- CVE-2023-22515: Atlassian Confluence Data Center and Server Broken Access Control Vulnerability
- CVE-2022-36804: Atlassian Bitbucket Server and Data Center Command Injection Vulnerability
Data from NVD, CISA KEV, FIRST EPSS and vendor advisories. Updated 29 Oct 2026.