Security Advisory

CVE-2026-86112

5.4
MEDIUM

Vulnerability Description

BookWyrm through 0.9.1 fails to validate user visibility permissions in the Favorite and Unfavorite views, allowing authenticated attackers to favorite or unfavorite followers-only and direct statuses they cannot access. Attackers can POST to the favorite endpoint with a status ID to create unauthorized interactions, trigger ActivityPub broadcasts, and enumerate private status IDs through response differentiation.
Published Date September 5, 2026
Official Source NIST NVD Advisory