{"id":"CVE-2021-26086","published":"2021-08-16T01:15:06Z","modified":"2026-06-17T03:42:50Z","title":"Atlassian Jira Server and Data Center Path Traversal Vulnerability","vendor":"Atlassian","product":"Jira Server and Data Center","tier":"core","eol":null,"description":{"text":"Affected versions of Atlassian Jira Server and Data Center allow remote attackers to read particular files via a path traversal vulnerability in the /WEB-INF/web.xml endpoint. The affected versions are before version 8.5.14, from version 8.6.0 before 8.13.6, and from version 8.14.0 before 8.16.1.","provenance":"source","from":"NVD"},"summary":{"text":"A path traversal flaw in the /WEB-INF/web.xml endpoint of Atlassian Jira Server and Data Center lets remote attackers read particular files. An attacker needs only network access to the affected versions, with no authentication, no user interaction, and no special configuration required.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-31T12:59:25Z"},"cvss":{"score":5.3,"severity":"MEDIUM","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","provenance":"source","from":"NVD"},"epss":{"score":0.99999,"percentile":0.99993,"date":"2026-10-30","provenance":"source"},"kev":{"dateAdded":"2024-11-12","dueDate":"2024-12-03","ransomware":false,"requiredAction":"Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.","notes":"https://jira.atlassian.com/browse/JRASERVER-72695 ; https://nvd.nist.gov/vuln/detail/CVE-2021-26086","provenance":"source"},"vulncheckKev":{"dateAdded":"2023-11-18","exploitedFirstSeen":"2023-11-18","ransomware":false,"evidence":[{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-11-18&host_type=src&vulnerability=cve-2021-26086","date":"2023-11-18"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-11-22&host_type=src&vulnerability=cve-2021-26086","date":"2023-11-22"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-11-23&host_type=src&vulnerability=cve-2021-26086","date":"2023-11-23"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-11-24&host_type=src&vulnerability=cve-2021-26086","date":"2023-11-24"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-11-25&host_type=src&vulnerability=cve-2021-26086","date":"2023-11-25"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-11-28&host_type=src&vulnerability=cve-2021-26086","date":"2023-11-28"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-11-29&host_type=src&vulnerability=cve-2021-26086","date":"2023-11-29"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-12-06&host_type=src&vulnerability=cve-2021-26086","date":"2023-12-06"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-12-07&host_type=src&vulnerability=cve-2021-26086","date":"2023-12-07"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-12-08&host_type=src&vulnerability=cve-2021-26086","date":"2023-12-08"}],"evidenceTotal":456,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev 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2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"},{"name":"Actively_Exploited_Kev | Oct 19, 2026","url":"https://otx.alienvault.com/pulse/6ad4dda174e5797d0bd238b7","created":"2026-10-18"},{"name":"Actively_Exploited_Kev | Oct 18, 2026","url":"https://otx.alienvault.com/pulse/6ad38c22e1848f8189d1c121","created":"2026-10-17"}],"provenance":"machine"},"cwes":[{"id":"CWE-22","name":"Improper Limitation of a Pathname to a Restricted Directory"}],"references":[{"url":"http://packetstormsecurity.com/files/164405/Atlassian-Jira-Server-Data-Center-8.4.0-File-Read.html","tags":["Exploit","Third Party Advisory","VDB Entry"]},{"url":"https://jira.atlassian.com/browse/JRASERVER-72695","tags":["Issue Tracking","Vendor Advisory"]},{"url":"http://packetstormsecurity.com/files/164405/Atlassian-Jira-Server-Data-Center-8.4.0-File-Read.html","tags":["Exploit","Third Party Advisory","VDB Entry"]},{"url":"https://jira.atlassian.com/browse/JRASERVER-72695","tags":["Issue Tracking","Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-26086","tags":["US Government Resource"]}],"techniques":[{"id":"T1190","name":"Exploit Public-Facing Application","tactics":["initial-access"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Remote path traversal against public-facing Jira web endpoint","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"allow remote attackers to read particular files via a path traversal vulnerability","start":59,"end":141}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1005","name":"Data from Local System","tactics":["collection"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: 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