The Subscriptions feature in Open-Xchange Server before 6.20.7 rev14, 6.22.0 before rev13, and 6.22.1 before rev14 does not properly validate the publication-source URL, which allows remote authenticated users to trigger arbitrary outbound TCP traffic via a crafted Source field, as demonstrated by (1) an ftp: URL, (2) a gopher: URL, or (3) an http://127.0.0.1/ URL, related to a "Server-side request forging (SSRF)" issue.