CVE-2026-85719
The AsyncHttpClient (AHC) library allows Java applications to easily execute HTTP requests and asynchronously process HTTP responses. From 2.1.0 until 2.16.1 and 3.0.12, requests using an authenticated SOCKS proxy can expose the proxy's credentials to the origin because NettyRequestFactory and NettyRequestSender attach Proxy-Authorization without confirming that the request is being sent to an HTTP proxy. With preemptive proxy authentication, the header is attached to a plaintext HTTP request, exposing credentials such as directly reversible Basic credentials to the origin. With the default non-preemptive flow, a hostile origin can return a 407 response and ProxyUnauthorized407Interceptor sends the proxy credentials through the existing SOCKS tunnel, including NTLM, Kerberos, and SPNEGO credentials. Releases before 2.1.0 lack SOCKS proxy support. This issue is fixed in versions 2.16.1 and 3.0.12.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 7.5 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N- Weakness
- CWE-319
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-09-17
- Last modified
- 2026-09-18
- Sources
- NVD
References
- https://github.com/AsyncHttpClient/async-http-client/commit/4d887704dec22027310f66c81503226722e9bd23
- https://github.com/AsyncHttpClient/async-http-client/commit/718ed2e86126663a88ea3db7a88cbbf93f0069b5
- https://github.com/AsyncHttpClient/async-http-client/commit/abaa8bd260beda3b85825ff95069ed11eaf4ca8d
- https://github.com/AsyncHttpClient/async-http-client/commit/be439b2ec773d12d61914c238d3e8eeaa6f0ba21
- https://github.com/AsyncHttpClient/async-http-client/security/advisories/GHSA-x5w6-vm3f-pp6f