Improper Resource Shutdown or Release Affecting org.asynchttpclient:async-http-client package, versions [3.0.8,3.0.12)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published20 Sept 2026
- disclosed17 Sept 2026
- credithyperxpro
Introduced: 17 Sep 2026
NewCVE-2026-85718 (opens in a new tab)How to fix?
Upgrade org.asynchttpclient:async-http-client to version 3.0.12 or higher.
Overview
org.asynchttpclient:async-http-client is a maven plugin for the Async Http Client (AHC) classes.
Affected versions of this package are vulnerable to Improper Resource Shutdown or Release due to NettyConnectListener.onSuccess() in the Netty connect path. An attacker can exhaust maxConnections or maxConnectionsPerHost by repeatedly triggering TLS handshake failures before completion, causing each failed attempt to orphan a permit. When the limit is per-host, repeated failed handshakes against one host permanently lock the client out of that host; with a global limit, failures against one reachable host drain the shared pool and prevent new connections to other hosts.
Workarounds
- Leave
maxConnectionsandmaxConnectionsPerHostat their default unlimited values; this avoids the permit-leak condition entirely because no connection semaphore is enforced. - Avoid connecting to untrusted hosts that can deliberately or repeatedly fail the TLS handshake; this prevents an attacker from exhausting the connection permit pool and locking the client out of a host or all hosts.