CVE-2016-9487 | EpubCheck 4.0.1 is vulnerable to external XML entity processing attacks

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.

Published: 2018-07-13 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2016-9487 is rated Moderate Risk (41.5/100): CVSS High severity, with low exploitation likelihood (EPSS 0.13%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2016-9487

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-03-30 0.21% 0.13% -0.08%
2 2025-03-29 0.06% 0.21% +0.15%
3 2023-03-07 — 0.06% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-9487

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 [email protected]
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 6.4 [email protected]

Weakness enumeration for CVE-2016-9487

OS Trackers for CVE-2016-9487

vendor priority summary link
ubuntu medium CVE-2016-9487 medium priority: Ubuntu including 1 source packages (epubcheck), 20 status rows across 20 suites (artful, bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 17, DNE 1, needed 1, released 1. https://ubuntu.com/security/CVE-2016-9487

Affected software / configurations for CVE-2016-9487

Vendor Product Version Raw CPE
w3 epubcheck 4.0.1 cpe:2.3:a:w3:epubcheck:4.0.1:*:*:*:*:*:*:*

References for CVE-2016-9487

URL Tags
https://www.kb.cert.org/vuls/id/779243 Third Party Advisory US Government Resource
https://www.securityfocus.com/bid/94864/ Third Party Advisory VDB Entry
cvelogic Threat Intelligence