Other Users: If another user uploads your phone number to WhatsApp from their address book, or if another user reports you (e.g., for spam or abuse), WhatsApp receives information about you from them.
Third-Party Services: If you use third-party services that integrate with WhatsApp (e.g., backing up chats to Google Drive or iCloud), those services receive the data you choose to share with them (including your WhatsApp honduras phone number list messages, which are encrypted but stored by the cloud provider). When viewing content from services like YouTube or Facebook within WhatsApp, some technical information is shared to enable this.
Meta Companies: As part of Meta, WhatsApp receives information from other Meta companies for purposes like security, fighting spam, and providing integrated experiences if you've opted into Accounts Center (e.g., information about your interests from Facebook/Instagram to personalize Meta AI interactions).