CVE-2026-85718

CVE-2026-85718 · AsyncHttpClient: Connection permit leak on TLS handshake failure causes per-host denial of service

This page contains facts from public vulnerability sources. Check the original advisory before updating.

The AsyncHttpClient (AHC) library allows Java applications to easily execute HTTP requests and asynchronously process HTTP responses. From 3.0.8 until 3.0.12, a client with maxConnections or maxConnectionsPerHost set above zero leaks one connection permit whenever TLS connection establishment fails before the handshake completes. NettyConnectListener removes the partitionKeyLock permit from NettyResponseFuture before every failure path is bound to the channel closeFuture, so an abort can leave the permit unreleased. Repeated failures can permanently lock out one host under a per-host limit or drain the shared pool under a global limit, blocking later requests even when no connection remains open. The default unlimited connection setting is not affected. This issue is fixed in version 3.0.12.

CVSS 5.9 · Medium · EPSS 0.5%

Published

2026-09-17T15:58:40.719Z

Updated

2026-09-17T16:40:07.831Z

Stack: system

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