It is possible to add users who are not friends as co-hosts in group events, despite Facebook documentation stating that only friends can be added as co-hosts. The system only validates whether the user is a member of the group, but does not enforce the friendship requirement.
According to Facebook’s official documentation:
“You can only add Facebook friends as co-hosts.”
However, when creating an event inside a group, the application does not validate whether the selected co-host is a friend of the event creator. Instead, the system only checks whether the user is a member of the group.
As a result, any group member — including users who are not friends with the event creator — can be added as a co-host to the event. This behavior contradicts the documented restriction and may lead to unintended privilege assignment within group events.
Facebook Help Center documentation states that only friends can be added as co-hosts:
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https://web.facebook.com/help/215235325174804
Browser: Firefox
Operating System: Windows
1. User A creates a Facebook group.
2. User B visits the group and joins it.
3. User A creates a new event inside the group.
4. While creating the event, User A adds User B as a co-host.
5. Observe that the system allows adding User B as a co-host even though they are not friends with User A.
This issue allows group members who are not friends with the event creator to obtain co-host privileges, which may allow them to:
Since co-hosts have administrative capabilities over the event, the absence of a friendship validation may allow unintended users to obtain management privileges.
While the behavior may be intentional for group contexts, it contradicts the official documentation and can cause confusion and unintended permission assignment.
November 28, 2025: Submit report
November 28, 2025: Initial evaluation
Hi Abu Idris,
A member of Meta’s security team has seen your report and performed an initial evaluation. We will get back to you once we have more information to share.
Thanks,
MetaSecurity
March 11, 2026: N/A
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