CVE-2026-85718 (GCVE-0-2026-85718)

Vulnerability from cvelistv5 – Published: 2026-09-17 15:58 – Updated: 2026-09-17 16:40
VLAI
Title
AsyncHttpClient: Connection permit leak on TLS handshake failure causes per-host denial of service
Summary
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.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-17 16:39 UTC
CWE
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-772 - Missing Release of Resource after Effective Lifetime
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7926 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
AsyncHttpClient async-http-client Affected: >= 3.0.8, < 3.0.12
guessed Create a notification for this product.
Show details on NVD website
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