CVE-2026-71290

Name	CVE-2026-71290
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.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
httpcomponents-client (PTS)	bullseye	4.5.13-2	undetermined
	forky, sid, bookworm, trixie	4.5.14-1	undetermined
httpcomponents-core5 (PTS)	bookworm	5.2.1-1	vulnerable
	trixie	5.2.2-1	vulnerable
	forky, sid	5.4.3-1	vulnerable

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
httpcomponents-client	source	(unstable)	undetermined
httpcomponents-core5	source	(unstable)	(unfixed)

Notes

https://lists.apache.org/thread/bhf7g2zwpom2ohvwjjjlonc93br2s8vq
https://www.openwall.com/lists/oss-security/2026/08/13/6
check, claimed to affect only version 5.2 onwards