CVE-2026-86112
MediumCVSS 5.4Summary
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.
Risk Assessment
The risk includes privacy breach and potential disclosure of private status information, potentially leading to confidentiality violations.
Recommendation
Update BookWyrm to a version that properly checks visibility permissions in Favorite and Unfavorite views. Additionally, restrict access to these functions to authorized users only.
Other vulnerabilities in BookWyrm
See all- CVE-2026-86113Medium
BookWyrm through 0.9.1 contains an authorization bypass vulnerability in the edit_readthrough function that allows authenticated users to modify other users' reading records. Attackers can exploit sequential ReadThrough IDs to overwrite arbitrary users' start dates, finish dates, progress, and progress mode, affecting reading statistics and exported data.
- CVE-2026-86111Medium
BookWyrm through 0.9.1 fails to validate user visibility permissions in the status edit endpoint, allowing authenticated attackers to read followers-only and direct-message reviews by enumerating sequential status IDs. Attackers can access the raw content of restricted statuses through the edit view, bypassing the privacy protections documented for these message types.
Original NVD description (English source)
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.