CVE-2025-66511
MEDIUM
4.8
Our Analysis: General-Purpose
Our model has classified this vulnerability as relevant to General-Purpose Systems, helping your team prioritize efforts effectively.
Published Date
December 5, 2025
Last Modified
December 10, 2025
CVSS Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
Description
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.