Vulnerability · Published May 11, 2026 · Assigned by GitHub_M

CVE-2026-42887Audiobookshelf: Stored Cross-Site Scripting in Login Page Custom Message

Medium 4.5

In plain English

A medium-severity cross-site scripting in audiobookshelf from advplyr. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 18% of all known vulnerabilities).

Severity (CVSS 3.1)4.5Medium

Exploit odds (30 days)0.3%top 82.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

Audiobookshelf is a self-hosted audiobook and podcast server. Prior to 2.33.0, a stored cross-site scripting (XSS) vulnerability exists in the Login Page due to improper sanitization of the authLoginCustomMessage field of the /api/auth-settings endpoint. An attacker with administrative privileges can inject arbitrary HTML/JavaScript that will be rendered on the login page for all users. This vulnerability is fixed in 2.33.0.

Affected products (as reported)

Vendor	Product	Versions
advplyr	audiobookshelf	< 2.33.0

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:N/A:N

References

https://github.com/advplyr/audiobookshelf/security/advisories/GHSA-cx29-ghq2-9cm4 x_refsource_CONFIRM