CVE-2026-85718: medium-severity vulnerability in AsyncHttpClient async-http-client
AsyncHttpClient: Connection permit leak on TLS handshake failure causes per-host denial of service
Published
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.9epss 0.5%
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:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
AsyncHttpClient · async-http-clientRelated CVEs — AsyncHttpClient async-http-client
In the same product, most dangerous first.
CVE-2024-53990CRITICALAsyncHttpClient (AHC) library's `CookieStore` replaces explicitly defined `Cookie`sEPSS 0.7%CVE-2026-85721HIGHAsyncHttpClient: Unbounded HTTP/1.1 response decompression enables a decompression-bomb denial of serviceEPSS 0.6%CVE-2026-85717MEDIUMAsyncHttpClient: Client-wide realm credentials re-sent to a cross-origin redirect targetEPSS 0.5%CVE-2026-107227HIGHAsyncHttpClient: Unbounded WebSocket permessage-deflate decompression enables a decompression-bomb denial of service when compression is enabledEPSS 0.4%CVE-2026-40490MEDIUMAsyncHttpClient leaks authorization credentials to untrusted domains on cross-origin redirectsEPSS 0.4%CVE-2026-85716LOWAsyncHttpClient: SCRAM and Digest mutual-authentication responses are not verifiedEPSS 0.4%
References
https://github.com/AsyncHttpClient/async-http-client/commit/64eb57af52a003ae7f29a2f9f4502271bbb138ddhttps://github.com/AsyncHttpClient/async-http-client/issues/2189https://github.com/AsyncHttpClient/async-http-client/pull/2288https://github.com/AsyncHttpClient/async-http-client/security/advisories/GHSA-gcmv-gr82-6m8v