CVE-2025-66546

LOW

Nextcloud Calendar <4.7.19, 5.5.6, 6.0.1 - Info Disclosure

Title source: llm
STIX 2.1

Description

Nextcloud Calendar is a calendar app for Nextcloud. Prior to 4.7.19, 5.5.6, and 6.0.1, the calendar app allowed blindly booking appointments with a squential ID without known the appointment token. This vulnerability is fixed in 4.7.19, 5.5.6, and 6.0.1.

References (4)

Core 4

Scores

CVSS v3 3.3
EPSS 0.0001
EPSS Percentile 0.9%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-639
Status published
Products (2)
nextcloud/calendar 6.0.0 (7 CPE variants)
nextcloud/calendar 4.0.0 - 4.7.19
Published Dec 05, 2025
Tracked Since Feb 18, 2026