Skip to content
CVE PROGRAM SOURCE RECORD4.8 Medium

CVE-2025-66511

Nextcloud Calendar app used predictable proposal participant tokens

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.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

nextcloud security-advisories

  • >= 6.0.0-rc.1, < 6.0.3affected

References