Executive brief
Audiobookshelf is a self-hosted server used to manage and stream audiobooks and podcasts. A security flaw allows an administrator to inject malicious code into the login page that is shown to all users. If exploited, this could allow an attacker to steal the usernames and passwords of other users as they attempt to log in.
Technical details
A stored cross-site scripting (XSS) vulnerability exists in Audiobookshelf versions prior to 2.33.0. The vulnerability is located in the login page (login.vue) which uses the 'v-html' directive to render the 'authLoginCustomMessage' field from the '/api/auth-settings' endpoint without proper sanitization. An attacker with administrative privileges can submit a crafted request to this endpoint containing malicious JavaScript. When any user subsequently visits the login page, the script executes in their browser context, potentially allowing the attacker to intercept plaintext credentials from the login form. The issue is resolved in version 2.33.0.
Affected products
- advplyr Audiobookshelf < 2.33.0
Timeline
- 2026-04-28: advisory: GitHub Security Advisory published by the vendor
- 2026-05-11: disclosed: CVE published to NVD