HTTPX2: Secure WebSocket traffic sent without TLS through SOCKS proxies (CVE-2026-84381) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-84381

HTTPX2: Secure WebSocket traffic sent without TLS through SOCKS proxies

Answer in brief

CVE-2026-84381 records a Unknown severity vulnerability in HTTPX2: Secure WebSocket traffic sent without TLS through SOCKS proxies. The current sources do not mark it as known exploited. The current feed maps pydantic/httpcore2 (generic), pydantic/httpx2 (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 2, 2026Updated Sep 2, 2026Source checked Sep 2, 2026First seen by HOL Sep 2, 2026Material review Sep 2, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Not reported

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps pydantic/httpcore2 (generic), pydantic/httpx2 (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
pydantic/httpcore2generic	< 2.10.0	Not reported
pydantic/httpx2generic	>= 2.6.0, < 2.10.0	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for pydantic/httpcore2, pydantic/httpx2.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Sep 2, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 2, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 2, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.