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CVE-2026-21589

high CISA KEV

Atlassian Multiple Products Files or Directories Accessible to External Parties Vulnerability

Vendor / product: Atlassian — Multiple Products

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.

CVSS
7.5
7.5 (CVSS v3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Severity source: NVD CVSS v3.1 (nvd@nist.gov)
Timeline (UTC)
Published: 2026-10-05 22:16
Modified: 2026-10-26 10:10
NVD status: Analyzed
Last synced 1 day ago
Verified against the source API 2026-10-27 07:07 UTC
Exploitation
Listed in CISA KEV
Added 2026-10-15 · due 2026-10-18
Known ransomware use: Unknown

Required action (CISA)

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.

Affected products

atlassian / bitbucket_data_center ≥7.17.0 <9.4.26, ≥9.5.0 <10.2.8, ≥10.3.0 <10.5.1
atlassian / bitbucket_server ≥4.6.0 ≤8.14.6
atlassian / confluence_data_center ≥5.10.0 <9.2.26, ≥9.3.0 <10.2.19
atlassian / crowd ≥2.11.0 <6.3.7, ≥7.0.0 <7.0.3, ≥7.1.0 <7.1.7, ≥7.2.0 <7.2.4
atlassian / jira_data_center ≥7.1.0 <9.12.40, ≥9.13.0 <10.3.26, ≥10.4.0 <11.3.12
atlassian / jira_service_desk ≥3.1.0 ≤4.13.27
atlassian / jira_service_management ≥4.14.0 <5.12.40, ≥5.13.0 <10.3.26, ≥10.4.0 <11.3.12
atlassian / bamboo ≥7.0.1 <10.2.24, ≥11.0.0 <12.1.12
atlassian / crucible <4.9.15
atlassian / fisheye <4.9.15

Weakness classification (CWE)

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

Vendor advisory: https://jira.atlassian.com/browse/BAM-26567
Vendor advisory: https://jira.atlassian.com/browse/BSERV-20604
Vendor advisory: https://jira.atlassian.com/browse/CONFSERVER-104488
Vendor advisory: https://jira.atlassian.com/browse/CRUC-8741
Vendor advisory: https://jira.atlassian.com/browse/CWD-6610
Vendor advisory: https://jira.atlassian.com/browse/FE-7583
Vendor advisory: https://jira.atlassian.com/browse/JRASERVER-79546
Vendor advisory: https://jira.atlassian.com/browse/JSDSERVER-16809
Patch / mitigation: https://jira.atlassian.com/browse/BAM-26567
Patch / mitigation: https://jira.atlassian.com/browse/BSERV-20604
Patch / mitigation: https://jira.atlassian.com/browse/CONFSERVER-104488
Patch / mitigation: https://jira.atlassian.com/browse/CRUC-8741
Patch / mitigation: https://jira.atlassian.com/browse/CWD-6610
Patch / mitigation: https://jira.atlassian.com/browse/FE-7583
Patch / mitigation: https://jira.atlassian.com/browse/JRASERVER-79546
Patch / mitigation: https://jira.atlassian.com/browse/JSDSERVER-16809

References

Data sources

CISA KEV — fetched 2026-10-27 06:50 UTC · record ↗
NVD CVE API 2.0 — fetched 2026-10-27 07:07 UTC · record ↗

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