{"id":"CVE-2021-26084","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-26084","generatedAt":"2026-10-31T14:14:27.713Z","title":"Atlassian Confluence Server and Data Center Object-Graph Navigation Language (OGNL) Injection Vulnerability","description":"In affected versions of Confluence Server and Data Center, an OGNL injection vulnerability exists that would allow an unauthenticated attacker to execute arbitrary code on a Confluence Server or Data Center instance. The affected versions are before version 6.13.23, from version 6.14.0 before 7.4.11, from version 7.5.0 before 7.11.6, and from version 7.12.0 before 7.12.5.","published":"2021-08-30T07:15:07.000Z","lastModified":"2026-06-17T03:42:50.000Z","status":"Analyzed","sourceIdentifier":"security@atlassian.com","cvss":{"version":"3.1","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-917"],"affected":["atlassian/confluence data center","atlassian/confluence server"],"epss":{"score":0.99999,"percentile":0.99993,"date":"2026-10-30","history":[]},"kev":{"listed":true,"dateAdded":"2021-11-03","dueDate":"2021-11-17","knownRansomwareCampaignUse":"Known","notes":"Apply updates per vendor instructions.\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-26084"},"exploits":{"count":1,"verified":false,"firstPublished":"2021-09-01","source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[{"edbId":50243,"kind":"exploit","title":"Confluence Server 7.12.4 - 'OGNL injection' Remote Code Execution (RCE) (Unauthenticated)","url":"https://www.exploit-db.com/exploits/50243","sourceUrl":"https://gitlab.com/exploit-database/exploitdb/-/blob/main/exploits/java/webapps/50243.py","file":"exploits/java/webapps/50243.py","published":"2021-09-01","added":"2021-09-01","updated":"2021-09-01","author":"Fellipe Oliveira","type":"webapps","platform":"java","port":null,"verified":false,"codes":["CVE-2021-26084"],"tags":null,"aliases":null,"applicationUrl":null,"screenshotUrl":null,"referenceUrl":null}]},"verdict":{"level":"urgent","text":"Known to be exploited in the wild (CISA KEV, CISA remediation deadline 17 November 2021). Treat as an emergency change: patch or isolate now, then hunt for prior compromise."},"changes":[],"references":[{"url":"http://packetstormsecurity.com/files/167449/Atlassian-Confluence-Namespace-OGNL-Injection.html","tags":["Exploit","Third Party Advisory","VDB Entry"],"source":"security@atlassian.com"},{"url":"https://jira.atlassian.com/browse/CONFSERVER-67940","tags":["Issue Tracking","Patch","Vendor Advisory"],"source":"security@atlassian.com"},{"url":"http://packetstormsecurity.com/files/167449/Atlassian-Confluence-Namespace-OGNL-Injection.html","tags":["Exploit","Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://jira.atlassian.com/browse/CONFSERVER-67940","tags":["Issue Tracking","Patch","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-26084","tags":["US Government Resource"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-26084","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."}