XSS in Advplyr Audiobookshelf

CVE-2026-27973

Audiobookshelf is a self-hosted audiobook and podcast server. A stored cross-site scripting (XSS) vulnerability exists in versions prior to 0.12.0-beta of the Audiobookshelf mobile application that allows arbitrary JavaScript execution through malicious library metadata. Attackers with library modification privileges can execute code in victim users' browsers/WebViews, potentially leading to session hijacking, data exfiltration, and unauthorized access to native device APIs. The issue is fixed in audiobookshelf-app version 0.12.0-beta, corresponding to audiobookshelf version 2.12.0.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.0 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (18.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 19th percentile — 18.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-27973: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-27973?
CVE-2026-27973 is a medium-severity vulnerability in Advplyr Audiobookshelf, classified under Cross-site Scripting. CVSS score: 4.0/10. Published 2026-02-26.
How severe is CVE-2026-27973?
Medium severity. CVSS v3 base score is 4.0 out of 10.