CVE-2026-71290: Improper Certificate Validation

August 11, 2026 (updated September 24, 2026)

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.

References

lists.apache.org/thread/bhf7g2zwpom2ohvwjjjlonc93br2s8vq
nvd.nist.gov/vuln/detail/CVE-2026-71290

Code Behaviors & Features

Detect and mitigate CVE-2026-71290 with GitLab Dependency Scanning

Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Learn more about Dependency Scanning →