p PatchFirst

CVE-2026-84381

CVE-2026-84381 · HTTPX2: Secure WebSocket traffic sent without TLS through SOCKS proxies

This page contains facts from public vulnerability sources. Check the original advisory before updating.

HTTPX2 is a next generation HTTP client for Python. Prior to 2.10.0, httpcore2 fails to start TLS in src/httpcore2/httpcore2/_sync/socks_proxy.py and src/httpcore2/httpcore2/_async/socks_proxy.py when the remote origin uses wss through a SOCKS5 proxy because the TLS upgrade condition only recognizes https. HTTPX2 exposes the flaw through Client.websocket() and AsyncClient.websocket() from 2.6.0 through 2.9.1, so the opening handshake, query parameters, Authorization headers, cookies, and subsequent frames can cross the proxy path in plaintext without certificate verification. An attacker controlling or observing that path can read or modify traffic and impersonate the WebSocket server. This issue is fixed in httpcore2 2.10.0 and HTTPX2 2.10.0.

CVSS 8.1 · High · EPSS 0.1% · Fix available

Published
Updated

Stack: system · python

Affected products and versions

  • httpx2

    Versions
    • >= 2.6.0, < 2.10.0: Affected

    No fix published

  • httpcore2

    Versions
    • < 2.10.0: Affected

    No fix published

  • httpcore2 PyPI

    Versions
    • 0.0.0
    • 2.0.0
    • 2.0.0b1
    • 2.1.0
    • 2.2.0
    • 2.3.0
    • 2.4.0
    • 2.5.0
    • 2.6.0
    • 2.7.0
    • 2.8.0
    • 2.9.0
    • 2.9.1
    Affected ranges
    • ECOSYSTEM: < 2.10.0

    Update to 2.10.0

  • httpx2 PyPI

    Versions
    • 2.6.0
    • 2.7.0
    • 2.8.0
    • 2.9.0
    • 2.9.1
    Affected ranges
    • ECOSYSTEM: ≥ 2.6.0, < 2.10.0

    Update to 2.10.0

  • python-httpx2 Ubuntu:26.10

    Versions
    • 2.5.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

Check your server →