Nextcloud: >> Calendar >> 4.2.1 Security Vulnerabilities
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.
CVSS Score
3.3
EPSS Score
0.0
Published
2025-12-05
Nextcloud Calendar is a calendar app for Nextcloud. Prior to 4.7.17 and 5.2.4, when a malicious user creates a calendar event with a crafted attachment that links to a download link of a file on the same Nextcloud server, the file would be downloaded without the user confirming the action. This vulnerability is fixed in 4.7.17 and 5.2.4.
CVSS Score
5.7
EPSS Score
0.0
Published
2025-12-05
Nextcloud/Cloud is a calendar app for Nextcloud. An attacker can gain access to stacktrace and internal paths of the server when generating an exception while editing a calendar appointment. It is recommended that the Nextcloud Calendar app is upgraded to 4.5.3
CVSS Score
3.5
EPSS Score
0.001
Published
2023-12-22
Nextcloud calendar is a calendar app for the Nextcloud server platform. Due to missing precondition checks the server was trying to validate strings of any length as email addresses even when megabytes of data were provided, eventually making the server busy and unresponsive. It is recommended that the Nextcloud Calendar app is upgraded to 4.4.4. The only workaround for users unable to upgrade is to disable the calendar app.
CVSS Score
4.3
EPSS Score
0.001
Published
2023-10-16
Calendar app for Nextcloud easily sync events from various devices with your Nextcloud. Some internal paths of the website are disclosed when the SMTP server is unavailable. It is recommended that the Calendar app is updated to 3.5.5 or 4.2.3
CVSS Score
2.6
EPSS Score
0.002
Published
2023-05-30