CVE-2016-4003

Cross-site scripting (XSS) vulnerability in the URLDecoder function in JRE before 1.8, as used in Apache Struts 2.x before 2.3.28, when using a single byte page encoding, allows remote attackers to inject arbitrary web script or HTML via multi-byte characters in a url-encoded parameter.

Published: 2016-04-12 Last update: 2026-05-06 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2016-4003 is rated Moderate Risk (62.9/100): CVSS Medium severity, with high exploitation likelihood (EPSS 12.02%, 96th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +9.39% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize 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-2016-4003

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 2026-06-15 2.63% 12.02% +9.39%
2 2026-03-17 2.18% 2.63% +0.45%
3 2026-03-04 — 2.18% —

Full EPSS history (14 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-4003

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.1 3.0 MEDIUM
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
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:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 2.7 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:N 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:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2016-4003

GitHub Security Advisory for CVE-2016-4003

GHSA-m3x6-9v6h-4g28 · Severity: medium · Ecosystem: maven — Cross-site Scripting in Apache Struts

OS Trackers for CVE-2016-4003

vendor priority summary link
redhat medium — https://access.redhat.com/security/cve/CVE-2016-4003
suse medium CVE-2016-4003 severity moderate: SUSE including 3 source package names (struts, struts-javadoc, struts-manual), 4 product×package rows across 2 product lines (SUSE Linux Enterprise Software Development Kit 11 SP4, SUSE Manager Server 2.1): Known Not Affected 4. https://www.suse.com/security/cve/CVE-2016-4003/
ubuntu medium CVE-2016-4003 medium priority: Ubuntu including 1 source packages (libstruts1.2-java), 10 status rows across 10 suites (artful, bionic, cosmic, precise, trusty, upstream, wily, xenial, yakkety, zesty): DNE 8, ignored 1, needs-triage 1. https://ubuntu.com/security/CVE-2016-4003

Affected software / configurations for CVE-2016-4003

Vendor Product Version Raw CPE
apache struts >= 2.0.0, <= 2.3.24.1 cpe:2.3:a:apache:struts:*:*:*:*:*:*:*:*

References for CVE-2016-4003

cvelogic Threat Intelligence