CVE-2023-48304: Nextcloud Server

Medium severity, CVSS 4.3. EPSS: 0.6% chance of exploitation in the next 30 days.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 25.0.0 and prior to versions 25.0.11, 26.0.6, and 27.1.0 of Nextcloud Server and starting in version 22.0.0 and prior to versions 22.2.10.16, 23.0.12.11, 24.0.12.7, 25.0.11, 26.0.6, and 27.1.0 of Nextcloud Enterprise Server, an attacker could enable and disable the birthday calendar for any user on the same server. Nextcloud Server 25.0.11, 26.0.6, and 27.1.0 and Nextcloud Enterprise Server 22.2.10.16, 23.0.12.11, 24.0.12.7, 25.0.11, 26.0.6, and 27.1.0 contain patches for this issue. No known workarounds are available.

Affected products

• Nextcloud Nextcloud Server: from 22.0.0, up to and including 22.2.10.16; from 23.0.0, before 23.0.12.11 (fixed in 23.0.12.11); from 24.0.0, before 24.0.12.7 (fixed in 24.0.12.7); from 25.0.0, before 25.0.11 (fixed in 25.0.11); from 26.0.0, before 26.0.6 (fixed in 26.0.6); from 27.0.0, before 27.1.0 (fixed in 27.1.0)

Published 2023-11-21. Last modified 2026-06-17.