{"id":"CVE-2026-58446","state":"PUBLISHED","title":"Presenton < 0.8.8-beta - Authentication Bypass of Session Auth via Unprotected MCP Endpoint","description":"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 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).","publishedAt":"2026-06-30T21:05:15.949Z","updatedAt":"2026-07-14T21:35:05.970Z","severity":{"score":6.9,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["presenton presenton"],"affected":[{"vendor":"presenton","product":"presenton","packageURL":"pkg:github/presenton/presenton","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"0.8.8-beta","versionType":"custom"}],"repo":"https://github.com/presenton/presenton"}],"references":["https://github.com/presenton/presenton/releases/tag/electron-v0.8.8-beta","https://github.com/presenton/presenton/issues/678","https://github.com/presenton/presenton/pull/679","https://github.com/presenton/presenton/commit/a1103dcef3c761cc8bab44e2862c81a49969abd7","https://www.vulncheck.com/advisories/presenton-beta-authentication-bypass-of-session-auth-via-unprotected-mcp-endpoint"],"weaknesses":["CWE-306"],"ingestedAt":"2026-10-29T20:12:24.861Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/58xxx/CVE-2026-58446.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-58446","state":"PUBLISHED","datePublished":"2026-06-30T21:05:15.949Z","dateUpdated":"2026-07-14T21:35:05.970Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-06-30T19:09:07.025Z"},"containers":{"cna":{"title":"Presenton < 0.8.8-beta - Authentication Bypass of Session Auth via Unprotected MCP Endpoint","descriptions":[{"lang":"en","value":"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 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)."}],"affected":[{"vendor":"presenton","product":"presenton","packageURL":"pkg:github/presenton/presenton","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"0.8.8-beta","versionType":"custom"}],"repo":"https://github.com/presenton/presenton"}],"references":[{"url":"https://github.com/presenton/presenton/releases/tag/electron-v0.8.8-beta","name":"Release Notes","tags":["release-notes"]},{"url":"https://github.com/presenton/presenton/issues/678","name":"Researcher Disclosure","tags":["technical-description","exploit"]},{"url":"https://github.com/presenton/presenton/pull/679","name":"Maintainer PR","tags":["issue-tracking"]},{"url":"https://github.com/presenton/presenton/commit/a1103dcef3c761cc8bab44e2862c81a49969abd7","name":"Fix Commit","tags":["patch"]},{"url":"https://www.vulncheck.com/advisories/presenton-beta-authentication-bypass-of-session-auth-via-unprotected-mcp-endpoint","tags":["third-party-advisory"]}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV3_1":{"attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"LOW","availabilityImpact":"LOW","version":"3.1","baseSeverity":"MEDIUM","baseScore":6.5,"vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L"}},{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","subConfidentialityImpact":"NONE","vulnIntegrityImpact":"LOW","subIntegrityImpact":"NONE","vulnAvailabilityImpact":"LOW","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","version":"4.0","baseSeverity":"MEDIUM","baseScore":6.9,"vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-306","lang":"en","description":"Missing Authentication for Critical Function","type":"CWE"}]}],"providerMetadata":{"shortName":"VulnCheck","orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateUpdated":"2026-07-14T21:35:05.970Z"},"tags":["x_open-source"],"datePublic":"2026-06-16T00:00:00.000Z","cpeApplicability":[{"nodes":[{"operator":"OR","cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:presenton:presenton:*:*:*:*:*:*:*:*","versionEndExcluding":"0.8.8-beta"}]}]}],"credits":[{"lang":"en","value":"George Chen","type":"finder"}],"x_generator":{"engine":"vulncheck-endgame"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/presenton/presenton/issues/678","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-01T13:58:23.292499Z","id":"CVE-2026-58446","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-07-01T13:58:28.447Z"}}]}}}