CVE-2026-42451: medium-severity vulnerability in grimmory-tools grimmory
Grimmory: Stored XSS via Malicious EPUB Enables Session Token Theft
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.3epss 0.1%
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.
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:L
Affected products
grimmory-tools · grimmoryRelated CVEs — grimmory-tools grimmory
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