CVE-2026-85718CWE-400CWE-772denial-of-service

CVE-2026-85718

Medium · published September 17, 2026

CVSS v3.1
5.9
EPSS
1%
Percentile
44.2
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.9 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00533 · 44.2th percentile
Weaknesses
CWE-400 · Uncontrolled Resource Consumption; CWE-772 · Missing Release of Resource after Effective Lifetime
Published
2026-09-17T20:18Z
References (4)
EPSS history
Timeline
  • 19 SEP 03:54Z
    EPSS moved — → 0%
    epss
  • 17 SEP 15:58Z
    AsyncHttpClient: Connection permit leak on TLS handshake failure causes per-host denial of service
    cvelistv5