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.

INFO

Published Date :

2025-12-05T16:42:30.236Z

Last Modified :

2025-12-05T16:53:52.674Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2025-66511 vulnerability.

Vendors Products
Nextcloud
  • Calendar
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2025-66511.

URL Resource
https://github.com/nextcloud/calendar/commit/8de14ae87f321f5f09280d9895a27d54d24f33fb cve-icon cve-icon
https://github.com/nextcloud/calendar/pull/7659 cve-icon cve-icon
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-whm3-vv55-gf27 cve-icon cve-icon
https://hackerone.com/reports/3385434 cve-icon cve-icon
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CVSS Vulnerability Scoring System

Detailed values of each vector for above chart.
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