Vulnerability 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.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- http://github.com/grimmory-tools/grimmory/releases/tag/v2.3.1
- https://github.com/grimmory-tools/grimmory/security/advisories/GHSA-frv6-5wq5-9p
FAQ
What is CVE-2026-42451?
CVE-2026-42451 is a vulnerability with a CVSS score of 6.3 (MEDIUM). 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 JavaS...
How severe is CVE-2026-42451?
CVE-2026-42451 has been rated MEDIUM with a CVSS base score of 6.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-42451?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.