CVE-2026-84381

Publication date 3 September 2026

Last updated 4 September 2026


Ubuntu priority

Cvss 3 Severity Score

8.1 · High

Score breakdown

Description

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.

Status

Package Ubuntu Release Status
python-httpx2 26.04 LTS resolute Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release

Severity score breakdown

CVSS version: CVSS v3.0

Base score 8.1 · High

Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N


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