Description
The Groups plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 3.7.0 via the 'group_id' parameter of the group_join function due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with Subscriber-level access and above, to register for groups other than ones set in the shortcode.
References3
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 14 · as of 10 November 2026
- CWE
- CWE-639
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.