{"id":"CVE-2026-58446","title":"Presenton < 0.8.8-beta - Authentication Bypass of Session Auth via Unprotected MCP Endpoint","summary":"Presenton before 0.8.8-beta bundles an MCP server that, on server/Docker deployments configured with session authentication (AUTH_USERNAME/AUTH_PASSWORD), is reachable unauthenticated at /mcp because the nginx front-end does not apply th…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L","cvssSource":"cna","cwe":["CWE-306"],"vendor":"presenton","product":"presenton","affected":["presenton < 0.8.8-beta"],"ssvc":{"exploitation":"poc","automatable":"yes","technicalImpact":"partial","timestamp":"2026-07-01T13:58:23.292499Z"},"exploitAvailable":true,"published":"2026-06-30","updated":"2026-11-08","sourceUpdated":"2026-11-08T14:07:00.877Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-58446","references":[{"url":"https://github.com/presenton/presenton/releases/tag/electron-v0.8.8-beta","label":"presenton electron-v0.8.8-beta Release Notes"},{"url":"https://github.com/presenton/presenton/issues/678","label":"Researcher Disclosure"},{"url":"https://github.com/presenton/presenton/pull/679","label":"Maintainer PR"},{"url":"https://github.com/presenton/presenton/commit/a1103dcef3c761cc8bab44e2862c81a49969abd7","label":"Fix Commit"},{"url":"https://www.vulncheck.com/advisories/presenton-beta-authentication-bypass-of-session-auth-via-unprotected-mcp-endpoint"}],"tags":["cve.org","exploit-available"],"epss":0.00703,"epssPercentile":0.5354,"ingestedAt":"2026-11-08T14:51:22.294Z","slug":"CVE-2026-58446","body":"## Overview\n\nPresenton before 0.8.8-beta bundles an MCP server that, on server/Docker deployments configured with session authentication (AUTH_USERNAME/AUTH_PASSWORD), is reachable unauthenticated at /mcp because the nginx front-end does not apply the auth_request gate to that path and the MCP server auto-mints a valid internal session token for the configured user. A remote unauthenticated attacker can invoke MCP tools such as generate_presentation, performing authenticated application actions, consuming the operators configured LLM API keys, and creating presentations in the operators instance. The Electron desktop build is not affected (MCP disabled).\n\n## Affected\n\n- `presenton < 0.8.8-beta`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":35.8,"likelihood":0.1,"exploitation":12,"ransomware":0},"changes":[]}