Vulnerability Note VU#779243

EpubCheck 4.0.1 contains a XML external entity processing vulnerability

Original Release date: 13 Dec 2016 | Last revised: 14 Dec 2016


EpubCheck 4.0.1 is vulnerable to external XML entity processing attacks.


EpubCheck is a tool to validate that EPUB files follow the proper format. It can be used as a stand alone command line utility, or included in a project (most commonly being epub readers) as a library.

CWE-611: Improper Restriction of XML External Entity Reference ('XXE') - CVE-2016-9487
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.


A remote attacker may be able to access arbitrary files on a system, or cause the system execute arbitrary requests.


Apply an update

EpubCheck has released version 4.0.2 to address the vulnerability.

Vendor Information (Learn More)

VendorStatusDate NotifiedDate Updated
AdobeAffected-13 Dec 2016
AppleAffected-14 Dec 2016
International Digital Publishing ForumAffected13 Oct 201609 Dec 2016
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base 6.8 AV:N/AC:M/Au:N/C:P/I:P/A:P
Temporal 5.9 E:--/RL:OF/RC:C
Environmental 4.5 CDP:N/TD:M/CR:ND/IR:ND/AR:ND



Thanks to Craig Arendt for reporting this vulnerability.

This document was written by Trent Novelly.

Other Information

  • CVE IDs: CVE-2016-9487
  • Date Public: 13 Dec 2016
  • Date First Published: 13 Dec 2016
  • Date Last Updated: 14 Dec 2016
  • Document Revision: 13


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