CVE-2026-85718: AsyncHttpClient async-http-client · Uncontrolled Resource Consumption
Affects AsyncHttpClient async-http-clientSource CVE Database V5
Not known to be exploited · CVSS 5.9 Medium : upgrade to 3.0.12 when convenient.
Data as of 1 Nov 2026, 11:03 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 45% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 3.0.12
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 17 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 1 Nov 2026.
What to do
Upgrade AsyncHttpClient async-http-client to 3.0.12.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| AsyncHttpClientasync-http-client | Affected
| Fixed in
|
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AI-suggested
Upgrade AsyncHttpClient to version 3.0.12 or later, where this issue is fixed. No other mitigations are indicated. Patch status is confirmed fixed in 3.0.12.
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.
References
- github.com/AsyncHttpClient/async-http-client/security/advisories/GHSA-gcmv-gr82-6m8v (opens in a new tab)
- github.com/AsyncHttpClient/async-http-client/issues/2189 (opens in a new tab)
- github.com/AsyncHttpClient/async-http-client/pull/2288 (opens in a new tab)
- github.com/AsyncHttpClient/async-http-client/commit/64eb57af52a003ae7f29a2f9f4502271bbb138dd (opens in a new tab)