{"id":"CVE-2026-21587","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-21587","generatedAt":"2026-10-28T03:32:12.694Z","title":"This High severity Improper Authorization vulnerability was introduced in version 11.3.0 of Jira Service Management Data Center.","description":"This High severity Improper Authorization vulnerability was introduced in version 11.3.0 of Jira Service Management Data Center. \n\t\n\tThis Improper Authorization vulnerability, with a CVSS Score of 7.1, allows an authenticated attacker to gain unintended access and can lead to the exposure of resources or functionality, possibly providing attackers with sensitive information or even execute arbitrary code. \n\t\n\tAtlassian recommends that Jira Service Management Data Center customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions:\n\t\t\n\t\t* Jira Service Management Data Center 11.3: Upgrade to a release greater than or equal to 11.3.11\n\t\t\n\t\t\n\t\n\tSee the release notes (https://confluence.atlassian.com/servicemanagement/jira-service-management-release-notes-780083086.html). You can download the latest version of Jira Service Management Data Center from the download center (https://www.atlassian.com/software/jira/service-management/download-archives). \n\t\n\tThis vulnerability was reported via our Penetration Testing program.","published":"2026-09-15T17:17:12.000Z","lastModified":"2026-09-17T12:17:32.000Z","status":"Awaiting Analysis","sourceIdentifier":"security@atlassian.com","cvss":{"version":"4.0","score":7.1,"severity":"HIGH","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-285"],"affected":[],"epss":{"score":0.00445,"percentile":0.38555,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.45%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://confluence.atlassian.com/pages/viewpage.action?pageId=1822852209","source":"security@atlassian.com"},{"url":"https://jira.atlassian.com/browse/JSDSERVER-16747","source":"security@atlassian.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-21587","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."}