CVE-2026-85718

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

State
Published
Severity
5.9 Medium
Published
Sep 17, 2026
Updated
Sep 17, 2026
Reserved
Sep 4, 2026

Read the record on cve.org

Description

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.

Scores

CVSSScoreVectorSource
3.15.9 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HGitHub_M

Weaknesses

  • CWE-400 Uncontrolled Resource Consumption
  • CWE-772 Missing Release of Resource after Effective Lifetime

Affected Products

ProductVersions
async-http-clientAsyncHttpClient
  • >= 3.0.8, < 3.0.12Affected

References

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