Revive Adserver: campaign-zone linking lets users link other agencies' campaigns

An authorization bypass in campaign-zone linking in Revive Adserver 6.0.8 and earlier allows an authenticated manager, or a trafficker with zone-linking permissions, to associate another agency's campaign with their own zone. Campaign ownership checks are missing from the bulk-linking and single-link operations in zone-include.php and the XML-RPC campaign-linking method. Although agency filtering prevents foreign banners from being linked, the unauthorized association can expose the foreign campaign's name, type and identifier in the linked-campaign listing. The issue is fixed in Revive Adserver 6.0.9 by validating campaign ownership in the affected operations.