CVE-2018-3761: Nextcloud Server

High severity, CVSS 8.1. EPSS: 1.7% chance of exploitation in the next 30 days.

Nextcloud Server before 12.0.8 and 13.0.3 suffer from improper authentication on the OAuth2 token endpoint. Missing checks potentially allowed handing out new tokens in case the OAuth2 client was partly compromised.

Affected products

• Nextcloud Nextcloud Server: before 12.0.8 (fixed in 12.0.8); from 13.0.0, before 13.0.3 (fixed in 13.0.3)

Published 2018-07-05. Last modified 2026-06-17.