CVE-2026-58446
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk35th percentile - higher than 35% of all known CVEs
Summary
A vulnerability in Presenton before version 0.8.8-beta allows an unauthenticated remote attacker to invoke MCP tools such as generate_presentation by accessing the /mcp path without authentication. This occurs 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.
Risk Assessment
An attacker can perform authenticated application actions, consume the operator's configured LLM API keys, and create presentations in the operator's instance, leading to unauthorized resource usage and potential data leakage.
Recommendation
Immediately update Presenton to version 0.8.8-beta or later. Until the update is applied, block access to the /mcp path at the firewall or proxy level.
Other vulnerabilities in Presenton
See all- CVE-2026-120192Medium
A security vulnerability has been detected in Presenton up to 0.9.11-beta. It affects an unknown part of the /app_data file in the Desktop Authentication Middleware component and leads to information disclosure. The attack can be launched remotely, and a public exploit is already available.
- CVE-2026-120191High
A weakness has been identified in Presenton up to 0.9.11-beta in some unknown functionality of the API component, causing missing authentication. The attack can be initiated remotely, and the exploit has been made public. Upgrading to version 0.9.12-beta resolves the issue.
Original NVD description (English source)
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).
Vulnerability data from NVD (NIST) · CISA KEV · EPSS