Patchfirst
CVE-2026-21589 KEVPublic exploit High · 7.5 EPSS 99.5%

Atlassian Multiple Products Files or Directories Accessible to External Parties Vulnerability

Atlassian · Multiple Products

Summary

A flaw in Atlassian's Multiple Products family, affecting Bitbucket, Confluence, Jira Software, Jira Service Management, Bamboo, Crowd, Crucible and Fisheye Data Center releases, allows files within the web application root directory to be read by outside parties. An unauthenticated remote attacker with network access can retrieve a specific file, but only if they already know its exact name and path, since the flaw does not permit listing or enumerating directory contents; the impact is highest where sensitive files are present.

Official 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.

Breakdown
78.2 / 100
Exploited
Yes, in CISA KEV
Reports
0
Tactics
2/15

How an attack unfolds

Based on mappings. Select a step to see the evidence.
  1. How attackers get in

  2. What they do

First seen exploited 2 days after disclosure. Public exploit code (PoC-in-GitHub) appeared 1 day after disclosure.

  1. Disclosedday 0
  2. Public exploit codePoC-in-GitHub+1 day
  3. First seen exploitedVulnCheck KEV evidence+2 days
  4. Added to CISA KEVEU database agrees+10 days

CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.

techniques

2 , grouped by in kill-chain order, 2 cited passages 2

Initial AccessTA0001

Exploit Public-Facing Application T1190 Medium
AI mapping from the description · how it is exploited

Unauthenticated remote access to web application files

This Arbitrary File Access vulnerability allows an unauthenticated attacker to access specific files
From the official description (NVD) Original (opens in a new tab) ↗

CollectionTA0009

Data from Local System T1005 Medium
AI mapping from the description · primary impact

Reads local files from the host filesystem

access specific files within the web application root directory
From the official description (NVD) Original (opens in a new tab) ↗

Detection

0 rules for this CVE · 163 general rules for its techniques

Rules for this CVE

0 that reference CVE-2026-21589 directly.

CVE-specific rules are not available in this build. Search SigmaHQ ↗

Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.

What security researchers reported

Not named in any threat report yet

Also mentioned in 28 community threat pulses (AlienVault OTX)

Weaker evidence

Pulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.

References

10 links, grouped by NVD tag
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