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Atlassian · Multiple Products

CVE-2026-21589

Atlassian Multiple Products Files or Directories Accessible to External Parties Vulnerability

Exploited in attacks Critical 9.3 Attack chance: 99.5%
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What it is

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.

CISA: 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.

What to do

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.

Deadline for US federal agencies: October 18, 2026

Added to the CISA list
October 15, 2026
Published
October 5, 2026
Severity
Critical 9.3 CVSS 4.0
Chance of attacks in the next 30 days (EPSS)
99.5% in the top 0.1% of all known vulnerabilities
Weakness
CWE-552
More details
NVD · CVE.org · CISA
All references (8)

More exploited flaws from Atlassian

AddedVulnerabilityProductSeverityAttack chance
Nov 12, 2024Path TraversalCVE-2021-26086Jira Server and Data CenterMedium 5.3>99.9%
Jan 24, 2024Template InjectionCVE-2023-22527used by ransomwareConfluence Data Center and ServerCritical 10.0>99.9%
Nov 7, 2023Improper AuthorizationCVE-2023-22518used by ransomwareConfluence Data Center and ServerCritical 10.0>99.9%
Oct 5, 2023Broken Access ControlCVE-2023-22515used by ransomwareConfluence Data Center and ServerCritical 10.099.2%
Sep 30, 2022Command InjectionCVE-2022-36804Bitbucket Server and Data CenterHigh 8.899.1%
Jul 29, 2022Questions For Confluence App Hard-coded CredentialsCVE-2022-26138ConfluenceCritical 9.898%
Jun 2, 2022Confluence Server and Data Center Remote Code ExecutionCVE-2022-26134used by ransomwareConfluence Server/Data CenterCritical 9.8>99.9%
Mar 28, 2022Pre-Authorization Arbitrary File ReadCVE-2021-26085used by ransomwareConfluence ServerMedium 5.399.9%

All of them →

Sources: Known Exploited Vulnerabilities (CISA, public domain), CVE records (cve.org) and EPSS (FIRST). The chance of attacks is the EPSS estimate that someone will try to exploit the flaw in the next 30 days.