CVE-2025-66511

MediumCVSS 6.5/10Last modified Oct 18, 2026

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.

Metrics

CVSS 3.1 6.5/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Weakness enumeration

CWE-330

Affected software

No affected versions have been published.

Timeline

Published: Dec 5, 2025
Last modified: Oct 18, 2026
NVD status: Analyzed

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