Low (3.5) in nextcloud nextcloud server. EPSS 1.0% chance of exploitation in the next 30 days.
Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.11, 20.0.10, and 21.0.2, an attacker is able to convert a Files Drop link to a federated share. This causes an issue on the UI side of the sharing user. When the sharing user opens the sharing panel and tries to remove the "Create" privileges of this unexpected share, Nextcloud server would silently grant the share read privileges. The vulnerability is patched in versions 19.0.11, 20.0.10 and 21.0.2. No workarounds are known to exist.
Severity
CVSS 3.1
3.5 low
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N
EPSS
1.0% chance of exploitation in the next 30 days; higher than 63% of CVEs (scores of 2026-10-31)