Auth bypass in Advplyr Audiobookshelf

CVE-2026-42883

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.

Vulnerability class: Broken Access Control

EPSS: 0.002 (10.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-42883?
CVE-2026-42883 is a medium-severity vulnerability in Advplyr Audiobookshelf, classified under Incorrect Authorization. CVSS score: 6.5/10. Published 2026-05-11.
How severe is CVE-2026-42883?
Medium severity. CVSS v3 base score is 6.5 out of 10.