CVE-2026-77203 (GCVE-0-2026-77203)

Vulnerability from cvelistv5 – Published: 2026-09-26 17:28 – Updated: 2026-09-26 22:51
VLAI
Title
Groups <= 4.6.0 - Authenticated (Subscriber+) Privilege Escalation via 'groups_join' Shortcode
Summary
The Groups – Memberships and Access Control plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 4.6.0. This is due to the groups_join() function deriving group-join eligibility from the ambient post's author capabilities via the global $post->post_author rather than from the currently authenticated user's own capabilities, while simultaneously minting and returning a valid groups-join-data hash and WordPress nonce for the caller in the same response — eliminating all authorization barriers to self-enrollment. This makes it possible for authenticated attackers, with Subscriber-level access and above, to enroll themselves into any group including privileged groups carrying the groups_admin_groups capability, and to subsequently create and join a group containing every registered WordPress capability, effectively escalating their privileges to Administrator. Exploitation requires the attacker to supply an Administrator-authored post ID via the post_ID parameter of the authenticated wp_ajax_parse_media_shortcode handler in order to establish the privileged ambient post context used by the flawed authorization check.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-26 22:44 UTC
CWE
  • CWE-269 - Improper Privilege Management
Assigner
References
Impacted products
Vendor Product Version CPE status
itthinx Groups – Memberships and Access Control Affected: 0 , ≤ 4.6.0 (semver)
guessed Create a notification for this product.
Credits
daroo
Show details on NVD website
To clipboard 

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