CRITICAL · 9.1

CVE-2026-71290

Improper TLS hostname verification vulnerability in Apache HttpComponents Client 5.4 or newer. HostnameVerificationPolicy#BUILTIN setting has no effect when used with the async version of HttpClient. ...

Vulnerability Description

Improper TLS hostname verification vulnerability in Apache HttpComponents Client 5.4 or newer. HostnameVerificationPolicy#BUILTIN setting has no effect when used with the async version of HttpClient. An attacker that can intercept and modify traffic between the client and the server can impersonate the server by presenting a valid certificate for a different domain.  Please note the classic version of HttpClient is not affected by this vulnerability.  Affected users are recommended to upgrade to at least version 5.6.4, which fixes the issue.

CVSS Score

9.1

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE

Affected Products

VendorProductVersions
ApacheHttpclient>= 5.4, < 5.6.4

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-71290?

CVE-2026-71290 is a vulnerability with a CVSS score of 9.1 (CRITICAL). Improper TLS hostname verification vulnerability in Apache HttpComponents Client 5.4 or newer. HostnameVerificationPolicy#BUILTIN setting has no effect when used with the async version of HttpClient. ...

How severe is CVE-2026-71290?

CVE-2026-71290 has been rated CRITICAL with a CVSS base score of 9.1/10. This is considered a critical vulnerability requiring immediate attention.

Is there a patch for CVE-2026-71290?

Check the references section above for vendor advisories and patch information. Affected products include: Apache Httpclient.