CVE-2026-71290 Apache HttpComponents Client: TLS hostname verification silently disabled on the async transport (default config, MITM)
Attackers can perform man-in-the-middle attacks because TLS hostname verification is silently disabled in the async transport of Apache HttpComponents Client.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-71290?
CVE-2026-71290 is a critical vulnerability in Apache HttpComponents Client, published on 11 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-295
Which versions are affected by CVE-2026-71290?
It affects 1 product.
Products include Apache Httpclient.
How do I fix CVE-2026-71290?
Upgrade to a fixed version.
Is CVE-2026-71290 being exploited?
There is no known exploitation of CVE-2026-71290 in the wild and no public exploit code.
Other vulnerabilities in Apache HttpComponents Client
- CVE-2013-4366 Hostname verification in Apache HttpClient 4.3 was disabled by default
- CVE-2025-27820 Apache HttpComponents: PSL (Public Suffix List) validation bypass
- CVE-2026-40542 Apache HttpClient accepts SCRAM-SHA-256 authentication without proper mutual authentication verification
- CVE-2012-5783 Improper Certificate Validation in Apache Commons HttpClient
- CVE-2026-64607 Apache HttpComponents Client: Connection Leak on Content-Encoding Decode Error Leads to Pool Exhaustion DoS
Sources
Also known as CLEANSTART-2026-CI69537, CLEANSTART-2026-HN97324, CLEANSTART-2026-TI66876, CLEANSTART-2026-YT77949, CLEANSTART-2026-ZL64046, CLSA-2026-1787027808 and 4 more.