Vulnerabilidades do Go-shiori Shiori

go-shiori's DownloadBookmark (internal/core/download.go) fetches a caller-supplied bookmark URL using a plain http.Client with no custom DialContext or destination-IP validation (no IsLoopback, IsPrivate, IsUnspecified, or IsLinkLocalUnicast checks).

Shiori contains a privilege escalation vulnerability in the account update endpoint that allows authenticated users to modify the owner field without authorization checks. Attackers can escalate to administrator by submitting a crafted PATCH request with owner: true, then re-authenticate to obtain an admin JWT token granting full system access.