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CVE-2025-66511

Estado: AnalizadaMedia (6.5)—

Nextcloud Calendar is a calendar app for Nextcloud. Prior to 6.0.3, the Calendar app generates participant tokens for meeting proposals using a hash function, allowing an attacker to compute valid participant tokens, which allowed them to request details and submit dates in meeting proposals. The tokens are not purely random generated. This vulnerability is fixed in 6.0.3.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

Tecnologías afectadas (1)

Nextcloud — Calendar

CWE

Referencias

JSON original (NVD)

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  "id": "CVE-2025-66511",
  "cveTags": [],
  "metrics": {
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          "options": [
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          "version": "2.0.3",
          "timestamp": "2025-12-05T16:53:43.707700Z"
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  "lastModified": "2026-06-17T09:56:57.673",
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