CVE-2016-9487: w3 Epubcheck

High severity, CVSS 7.8. EPSS: 1.3% chance of exploitation in the next 30 days.

EpubCheck 4.0.1 does not properly restrict resolving external entities when parsing XML in EPUB files during validation. An attacker who supplies a specially crafted EPUB file may be able to exploit this behavior to read arbitrary files, or have the victim execute arbitrary requests on his behalf, abusing the victim's trust relationship with other entities.

Affected products

• w3 Epubcheck: version 4.0.1 only

Published 2018-07-13. Last modified 2026-06-17.