Quick answers
- Is CVE-2026-42887 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-42887 being exploited in the wild.
- How severe is CVE-2026-42887?
- Medium severity, with a CVSS score of 4.5, published 11 May 2026.
- Which products and versions are affected?
- Advplyr Audiobookshelf < 2.33.0.
- Is there a fix for CVE-2026-42887?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-42887 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-42887?
- Check whether you run Advplyr Audiobookshelf at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
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