CVE-2026-58446 (GCVE-0-2026-58446)

Vulnerability from cvelistv5 – Published: 2026-06-30 21:05 – Updated: 2026-06-30 21:05 X_Open Source
VLAI
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 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).
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
6.9 (Medium)
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
CWE
  • CWE-306 - Missing Authentication for Critical Function
Assigner
References
Impacted products
Vendor Product Version
presenton presenton Affected: 0 , < 0.8.8-beta (custom)
Create a notification for this product.
Date Public
2026-06-16 00:00
Credits
George Chen
Show details on NVD website
To clipboard 

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          "tags": [
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          "url": "https://github.com/presenton/presenton/issues/678"
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          "name": "Maintainer PR",
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          "url": "https://github.com/presenton/presenton/pull/679"
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          "name": "Fix Commit",
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          "url": "https://github.com/presenton/presenton/commit/a1103dcef3c761cc8bab44e2862c81a49969abd7"
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    "datePublished": "2026-06-30T21:05:15.949Z",
    "dateReserved": "2026-06-30T19:09:07.025Z",
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    "state": "PUBLISHED"
  },
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  "dataVersion": "5.2",
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  }
}


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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.