CVE-2026-58446 Details
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).
A vulnerability exists in Presenton versions prior to 0.8.8-beta, where the bundled MCP server is accessible unauthenticated at the '/mcp' endpoint. This issue arises in server or Docker deployments with session authentication enabled (AUTH_USERNAME/AUTH_PASSWORD). The Nginx front-end fails to enforce authentication for this path, allowing remote attackers to exploit the MCP tools, such as 'generate_presentation', which uses the operator's LLM API keys and creates presentations in their instance. The Electron desktop version is not affected as MCP is disabled.
Users can update to Presenton version 0.8.8-beta or later, where this vulnerability has been fixed.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Jun 30, 2026CISA-ADP
Assessed Jul 1, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/presenton/presenton/issues/678 | CISA-ADP | ExploitIssue TrackingTechnical DescriptionVendor |
| https://github.com/presenton/presenton/commit/a1103dcef3c761cc8bab44e2862c81a49969abd7 | [email protected] | Source CodeVendor |
| https://github.com/presenton/presenton/issues/678 | [email protected] | ExploitIssue TrackingTechnical DescriptionVendor |
| https://github.com/presenton/presenton/pull/679 | [email protected] | Issue TrackingVendor |
| https://github.com/presenton/presenton/releases/tag/electron-v0.8.8-beta | [email protected] | Release NotesVendor |
| https://www.vulncheck.com/advisories/presenton-beta-authentication-bypass-of-session-auth-via-unprotected-mcp-endpoint | [email protected] | AdvisoryBundleRemedy |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-306 | Missing Authentication for Critical Function | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| Presenton | <= 0.8.7-beta (semver) |
CPE
Remediation
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Change History
3 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jul 14, 2026 | CVE Modified | [email protected] |
| Jul 1, 2026 | CVE Modified | CISA-ADP |
| Jun 30, 2026 | New CVE Received | [email protected] |