CVE-2026-42883 Audiobookshelf: Cross-library file exfiltration via unscoped bulk download endpoint
Authenticated users can exfiltrate files from unauthorized libraries via the bulk download endpoint due to missing access controls.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-42883?
CVE-2026-42883 is a medium-severity missing authorization vulnerability in advplyr audiobookshelf, published on 11 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Audiobookshelf is a self-hosted audiobook and podcast server. Prior to 2.32.2, the GET /api/libraries/:id/download endpoint validates that the requesting user has access to the library specified in the URL path, but fetches downloadable items solely by attacker-provided IDs without constraining them to that library. An authenticated user with download permission and access to any one library can exfiltrate the full file contents of items belonging to any other library, including libraries they are explicitly denied access to. This vulnerability is fixed in 2.32.2.
Weakness: CWE-863
Which versions are affected by CVE-2026-42883?
How do I fix CVE-2026-42883?
No fix has been published for CVE-2026-42883 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-42883 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42883 exists.