{"id":"CVE-2026-77270","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-77270","generatedAt":"2026-10-28T02:10:33.806Z","title":"The server opens the selected file and uploads it to an Atlassian issue or page, allowing an MCP caller with upload access to disclose any file readable by the server process.","description":"MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the Jira and Confluence attachment upload tools treat caller-controlled file_path values as trusted server-local paths. The server opens the selected file and uploads it to an Atlassian issue or page, allowing an MCP caller with upload access to disclose any file readable by the server process. The advisory traces the vulnerable input and processing flow through confluence_upload_attachment, jira_upload_attachment, file_path, and open(file_path, \"rb\"), which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.","published":"2026-09-22T18:17:19.000Z","lastModified":"2026-09-28T13:35:22.000Z","status":"Analyzed","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":6.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N"},"cwe":["CWE-22"],"affected":["mcp-atlassian/mcp atlassian"],"epss":{"score":0.005,"percentile":0.42531,"date":"2026-10-26","history":[{"date":"2026-09-23","score":0.00481,"percentile":0.40618}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.50%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-09-22T18:17:19.000Z","detail":{"score":"6.5","severity":"MEDIUM","publishedAt":"2026-09-22T18:17:18.947Z"},"summary":"New CVE, medium severity (CVSS 6.5)."}],"references":[{"url":"https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460","tags":["Patch"],"source":"security-advisories@github.com"},{"url":"https://github.com/sooperset/mcp-atlassian/pull/1448","tags":["Issue Tracking","Patch"],"source":"security-advisories@github.com"},{"url":"https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0","tags":["Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-f26r-j276-ggg4","tags":["Exploit","Mitigation","Vendor Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-f26r-j276-ggg4","tags":["Exploit","Mitigation","Vendor Advisory"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-77270","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."}