CVE-2026-85718: CWE-400: Uncontrolled Resource Consumption in AsyncHttpClient async-http-client
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.
AI Analysis
Technical Summary
The AsyncHttpClient (AHC) library versions >=3.0.8 and <3.0.12 have an uncontrolled resource consumption vulnerability (CWE-400) due to leaking connection permits when TLS connection establishment fails before handshake completion. Specifically, the NettyConnectListener removes the partitionKeyLock permit from NettyResponseFuture before binding failure paths to the channel closeFuture, so an abort can leave the permit unreleased. This leak can cause a per-host or global connection limit to be exhausted, blocking subsequent requests even though no connections remain open. The default unlimited connection setting is unaffected. The vulnerability is resolved in version 3.0.12.
Potential Impact
Exploitation of this vulnerability can lead to denial of service by exhausting connection permits in the connection pool, preventing new connections to a host or globally. This results in blocking of legitimate requests due to resource exhaustion. There is no impact on confidentiality or integrity, only availability is affected.
Mitigation Recommendations
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.
CVE-2026-85718: CWE-400: Uncontrolled Resource Consumption in AsyncHttpClient async-http-client
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.
CVSS v3.1
Score 5.9medium
Affected software
AsyncHttpClient
async-http-client
pkg:maven/org.asynchttpclient/async-http-clientRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The AsyncHttpClient (AHC) library versions >=3.0.8 and <3.0.12 have an uncontrolled resource consumption vulnerability (CWE-400) due to leaking connection permits when TLS connection establishment fails before handshake completion. Specifically, the NettyConnectListener removes the partitionKeyLock permit from NettyResponseFuture before binding failure paths to the channel closeFuture, so an abort can leave the permit unreleased. This leak can cause a per-host or global connection limit to be exhausted, blocking subsequent requests even though no connections remain open. The default unlimited connection setting is unaffected. The vulnerability is resolved in version 3.0.12.
Potential Impact
Exploitation of this vulnerability can lead to denial of service by exhausting connection permits in the connection pool, preventing new connections to a host or globally. This results in blocking of legitimate requests due to resource exhaustion. There is no impact on confidentiality or integrity, only availability is affected.
Mitigation Recommendations
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.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-09-04T14:45:10.648Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6aac199655bf5e2cf5a38b7e
Added to database: 09/17/2026, 16:47:18 UTC
Last enriched: 09/17/2026, 17:01:28 UTC
Last updated: 09/18/2026, 00:25:38 UTC
Views: 12
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