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Vulnerability Intelligence

CVE-2026-21589

CriticalExploitedPublic exploitrejected

This is a vulnerability in Bitbucket Data Center, Confluence Data Center, Jira Service Management Data Center, Jira Software Data Center, Bamboo Data Center.

Published Oct 5, 2026 · Updated Oct 16, 2026 · Also known as EUVD-2026-92807, GHSA-gr66-x5pq-8g2g

Key Facts

Patch immediately
  • CVE-2026-21589 is a critical-severity vulnerability (CVSS 9.3 v4) affecting Bamboo (Atlassian), Bitbucket Data Center (Atlassian), Bitbucket Server (Atlassian) and 20 more products.
  • It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Oct 6, 2026. Public exploit code is available.
  • EPSS estimates a 13% probability of exploitation in the next 30 days.
  • Fixed versions are available, including Bamboo 10.2.24, Bamboo 12.1.12, Bitbucket Data Center 10.2.8.
  • Brandefense priority: patch immediately, because it is listed as exploited in the wild.

CVSS v4

9.3

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

EPSS (30-day exploit likelihood)

13%

Higher than 96.2% of all scored CVEs

Exploited in the wild

Yes

4 catalog listings

Public exploit code

Available

Proof-of-concept or weaponized module

Get the full CVE-2026-21589 brief as a PDF

Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.

Description

Rejected reason: This CVE's publication may have been a false positive or a mistake. As a result, we have rejected this record.

Known-Exploited Catalog Listings

CatalogAddedRemediation dueRansomware use
CISA KEVOct 15, 2026Oct 18, 2026Not reported
Industry KEV feedOct 7, 2026Oct 18, 2026Not reported
CIRCL KEVOct 6, 2026Oct 18, 2026Not reported
ENISA EUVDOct 15, 2026n/aNot reported

Required action: 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

42 affected entries in total
ProductAffected versionsFixed in
BambooAtlassianSee advisory10.2.24
Bitbucket Data CenterAtlassian>= All other versions9.4.26
Bitbucket ServerAtlassian>= All versions8.14.6
Confluence Data CenterAtlassian>= All other versions9.2.26
CrowdAtlassianSee advisory6.3.7
18 more affected products in the full CVE brief

Patched Releases

Bamboo

10.2.24, 12.1.12

Bitbucket Data Center

10.2.8, 10.5.1, 9.4.26

Bitbucket Server

8.14.6

Confluence Data Center

10.2.19, 9.2.26

Crowd

6.3.7, 7.0.3, 7.1.7, 7.2.4

Crucible

4.9.15

Fisheye

4.9.15

Jira Data Center

10.3.26, 11.3.12, 9.12.40

Jira Service Desk

4.13.27

Jira Service Management

10.3.26, 11.3.12, 5.12.40

Timeline

  1. Publicly disclosed

    Oct 5, 2026

  2. Added to CIRCL KEV

    Oct 6, 2026

  3. Added to Industry KEV feed

    Oct 7, 2026

  4. Added to CISA KEV

    Oct 15, 2026

  5. Added to ENISA EUVD

    Oct 15, 2026

  6. Last updated

    Oct 16, 2026

Weakness Type

  • CWE-552 Files or Directories Accessible to External Parties

References

7 more references in the full CVE brief

FAQ

Common Questions.

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