CVE-2025-66511

CWE-3302 documents2 sources
Severity
6.5MEDIUM
EPSS
0.0%
top 91.16%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
2
Nextcloud CalendarNextcloud Security-advisories
Timeline
PublishedDec 5

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.

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:NExploitability: 2.2 | Impact: 2.5

Affected Packages2 packages

▶NVDnextcloud/calendar6.0.0 — 6.0.3
▶CVEListV5nextcloud/security-advisories>= 6.0.0-rc.1, < 6.0.3

Patches

Patch: github.com ↗Patch: github.com ↗

🔴Vulnerability Details

1
CVEList
Nextcloud Calendar app used predictable proposal participant tokens↗2025-12-05
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