Summary
AsyncHttpClient: WebSocket proxy credentials sent to the origin server over a CONNECT tunnel
Advisory details
Impact
When a ws:// request is routed through an HTTP proxy with proxy authentication configured, the client tunnels the connection with an HTTP CONNECT, the same as it does for https://. Once the tunnel is open, the WebSocket upgrade request that follows is sent through the tunnel directly to the origin server, not to the proxy. The proxy-auth gate and the companion request-target selection keyed only on whether the URI was secured, which is false for ws://, so the tunnelled upgrade request incorrectly carried the proxy's Proxy-Authorization header and an absolute-form request target meant for the proxy. Any origin server reached over a proxied ws:// connection, or anyone positioned on the origin side of the wire, could recover the proxy credentials: directly for Basic, or as a replayable and offline-crackable response for Digest.
Affected versions
- 3.x: up to and including 3.0.11
- 2.x: up to and including 2.16.0
Patches
Fixed in 3.0.12 on the 3.x line and in 2.16.1 on the 2.x line. The preemptive Proxy-Authorization header and the absolute-form request target are no longer attached to a tunnelled ws:// upgrade; a ws:// request is now treated like wss://.
Workarounds
Do not use proxy authentication together with ws:// requests through an HTTP proxy, or use wss:// instead.
Details
The proxy-auth gate in NettyRequestFactory#newNettyRequest and the sibling branch in requestUri() did not exclude WebSocket URIs, even though the CONNECT-tunnelling check in NettyRequestSender already tunnels ws:// through CONNECT exactly like https://.
Note that 3.0.12 is itself affected by a separate issue, GHSA-rqf5-2wxv-rjf4, where a Digest challenge the client cannot read downgrades to Basic and sends the password in cleartext. Upgrade to 3.0.13 to pick up both fixes.
References
- https://github.com/advisories/GHSA-3wp9-xfwm-rjjf
- https://github.com/AsyncHttpClient/async-http-client/security/advisories/GHSA-3wp9-xfwm-rjjf
- https://nvd.nist.gov/vuln/detail/CVE-2026-107285
- https://github.com/AsyncHttpClient/async-http-client/commit/6e9cb75a9b7259353f983fc90ca28b1da3742e18
- https://github.com/AsyncHttpClient/async-http-client/commit/c4feab0f7f86d61505a48e40d383c8a375a22e18
- https://github.com/AsyncHttpClient/async-http-client/releases/tag/async-http-client-project-2.16.1
- https://github.com/AsyncHttpClient/async-http-client/releases/tag/async-http-client-project-3.0.12
Related vulnerabilities
All Supply chain →- CRITICALCVE-2026-107282
AsyncHttpClient: Replay to a different host sends the original host request and credentials to the new host
- HIGHCVE-2026-107231
AsyncHttpClient: Digest challenge without a usable nonce downgrades to Basic and sends the password in cleartext
- MEDIUMCVE-2026-85720
AsyncHttpClient sends origin credentials to the proxy on the plaintext CONNECT request
- HIGHGHSA-vx52-2968-3vc6
pnpm: Environment secrets exfiltrated via env-placeholder expansion in proxy settings read from an untrusted pnpm-workspace.yaml
- MEDIUMCVE-2026-55860
org.mariadb:r2dbc-mariadb vulnerable to cleartext password disclosure to a man-in-the-middle server (clear-text auth plugins not gated on a secure transport)
- MEDIUMCVE-2026-55857
org.mariadb.jdbc:mariadb-java-client has Cleartext Transmission of Sensitive Information and Insufficiently Protected Credentials