CVE-2013-4366

http/impl/client/HttpClientBuilder.java in Apache HttpClient 4.3.x before 4.3.1 does not ensure that X509HostnameVerifier is not null, which allows attackers to have unspecified impact via vectors involving hostname verification.

Published: 2017-10-30 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2013-4366 is rated High Risk (68.1/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 2.18%). 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-2013-4366

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 1.29% 2.18% +0.89%
2 2025-05-16 1.36% 1.29% -0.07%
3 2025-03-30 — 1.36% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2013-4366

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H 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:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
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.
 3.9 5.9 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/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:L)
Exploitation conditions are straightforward and predictable.
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.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2013-4366

GitHub Security Advisory for CVE-2013-4366

GHSA-pqwh-44jj-p5rm · Severity: critical · Ecosystem: maven — Hostname verification in Apache HttpClient 4.3 was disabled by default

OS Trackers for CVE-2013-4366

vendor priority summary link
debian not yet assigned CVE-2013-4366 not yet assigned priority: Debian including 1 source packages (httpcomponents-client), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2013-4366
ubuntu medium CVE-2013-4366 medium priority: Ubuntu including 1 source packages (httpcomponents-client), 5 status rows across 5 suites (artful, trusty, upstream, xenial, zesty): not-affected 4, released 1. https://ubuntu.com/security/CVE-2013-4366

Affected software / configurations for CVE-2013-4366

Vendor Product Version Raw CPE
apache httpclient 4.3 cpe:2.3:a:apache:httpclient:4.3:*:*:*:*:*:*:*
apache httpclient 4.3 cpe:2.3:a:apache:httpclient:4.3:alpha1:*:*:*:*:*:*
apache httpclient 4.3 cpe:2.3:a:apache:httpclient:4.3:beta1:*:*:*:*:*:*
apache httpclient 4.3 cpe:2.3:a:apache:httpclient:4.3:beta2:*:*:*:*:*:*

References for CVE-2013-4366

URL Tags
http://svn.apache.org/r1528614 Issue Tracking Patch Release Notes Vendor Advisory
http://www.apache.org/dist/httpcomponents/httpclient/RELEASE_NOTES-4.3.x.txt Issue Tracking Release Notes Vendor Advisory
cvelogic Threat Intelligence