{"id":"CVE-2026-21589","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-21589","generatedAt":"2026-10-23T21:16:56.886Z","title":"Atlassian Multiple Products Files or Directories Accessible to External Parties Vulnerability","description":"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.","published":"2026-10-05T22:16:58.000Z","lastModified":"2026-10-19T20:31:57.000Z","status":"Analyzed","sourceIdentifier":"security@atlassian.com","cvss":{"version":"4.0","score":9.3,"severity":"CRITICAL","vector":"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-552"],"affected":["atlassian/bitbucket data center","atlassian/bitbucket server","atlassian/confluence data center","atlassian/crowd","atlassian/jira data center","atlassian/jira service desk","atlassian/jira service management","atlassian/bamboo","atlassian/crucible","atlassian/fisheye"],"epss":{"score":0.12711,"percentile":0.96261,"date":"2026-10-22","history":[{"date":"2026-10-06","score":0.00738,"percentile":0.53045},{"date":"2026-10-07","score":0.01755,"percentile":0.77225},{"date":"2026-10-12","score":0.02777,"percentile":0.85995},{"date":"2026-10-16","score":0.12711,"percentile":0.96225}]},"kev":{"listed":true,"dateAdded":"2026-10-15","dueDate":"2026-10-18","knownRansomwareCampaignUse":"Unknown","notes":"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.\nhttps://confluence.atlassian.com/security/cve-2026-21589-arbitrary-file-access-vulnerability-impacts-multiple-products-1870495748.html?ref=labs.watchtowr.com ; ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-21589"},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"Known to be exploited in the wild (CISA KEV, CISA remediation deadline 18 October 2026). Treat as an emergency change: patch or isolate now, then hunt for prior compromise."},"changes":[{"kind":"scored","label":"Newly scored","at":"2026-10-19T21:00:19.000Z","detail":{"from":null,"score":"9.3","severity":"CRITICAL","fromSeverity":null},"summary":"Now scored CVSS 9.3 CRITICAL."},{"kind":"epss","label":"EPSS jump","at":"2026-10-16T00:00:00.000Z","detail":{"to":0.12711,"from":0.02777,"percentile":0.96225},"summary":"EPSS moved from 2.8% to 12.7% probability of exploitation in the next thirty days."},{"kind":"kev","label":"Added to KEV","at":"2026-10-15T00:00:00.000Z","detail":{"name":"Atlassian Multiple Products Files or Directories Accessible to External Parties Vulnerability","vendor":"Atlassian","dueDate":"2026-10-18","product":"Multiple Products","ransomware":"Unknown"},"summary":"Added to CISA KEV — known to be exploited; federal remediation due 2026-10-18."},{"kind":"new","label":"New CVE","at":"2026-10-05T22:16:58.000Z","detail":{"score":"9.3","severity":"CRITICAL","publishedAt":"2026-10-05T22:16:58.423Z"},"summary":"New CVE, critical severity (CVSS 9.3), EPSS 12.7%."}],"references":[{"url":"https://jira.atlassian.com/browse/BAM-26567","tags":["Issue Tracking","Mitigation","Vendor Advisory"],"source":"security@atlassian.com"},{"url":"https://jira.atlassian.com/browse/BSERV-20604","tags":["Issue Tracking","Mitigation","Vendor Advisory"],"source":"security@atlassian.com"},{"url":"https://jira.atlassian.com/browse/CONFSERVER-104488","tags":["Issue Tracking","Mitigation","Vendor Advisory"],"source":"security@atlassian.com"},{"url":"https://jira.atlassian.com/browse/CRUC-8741","tags":["Issue Tracking","Mitigation","Vendor Advisory"],"source":"security@atlassian.com"},{"url":"https://jira.atlassian.com/browse/CWD-6610","tags":["Issue Tracking","Mitigation","Vendor Advisory"],"source":"security@atlassian.com"},{"url":"https://jira.atlassian.com/browse/FE-7583","tags":["Issue Tracking","Mitigation","Vendor Advisory"],"source":"security@atlassian.com"},{"url":"https://jira.atlassian.com/browse/JRASERVER-79546","tags":["Issue Tracking","Mitigation","Vendor Advisory"],"source":"security@atlassian.com"},{"url":"https://jira.atlassian.com/browse/JSDSERVER-16809","tags":["Issue Tracking","Mitigation","Vendor Advisory"],"source":"security@atlassian.com"},{"url":"https://github.com/watchtowrlabs/watchTowr-vs-Atlassian-CVE-2026-21589","tags":["Third Party Advisory"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-21589","tags":["US Government Resource"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-21589","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}