CVE-2026-42451EPSS p3.3%

CVE-2026-42451CVE-2026-42451

Description

Grimmory is a self-hosted digital library. Prior to version 2.3.1, a stored cross-site scripting (XSS) vulnerability in Grimmory's browser-based EPUB reader allows an attacker to embed arbitrary JavaScript in a crafted EPUB file. When a victim opens the book, the script executes in their browser with full access to the Grimmory application's session context. This can enable session token theft and account takeover, including administrative access if an administrator opens the affected book. This issue has been patched in version 2.3.1.

Scoring

CVSS 6.3 ()
VectorCVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:L
EPSS0.15% probability of exploitation · percentile 3.3% · 2026-10-05T12:00:23Z
Last modified2026-07-24
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.