Secuno
ENNL
Book demo

CVE-2026-84381

HTTPX2 vulnerability

8.1 HIGHEPSS 0.11%
  1. Published2 Sept 2026

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.

CVSS 3.1 breakdown

Attack vectorAdjacent
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityNone
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

References

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

CVE-2026-919888.1
atomic-agents-stack before 1.1.0 accepts cleartext HTTP schemes in the HTTP MCP…
CVE-2026-696589.8
MQTT credentials and control traffic are transmitted in cleartext, exposing sensitive…
CVE-2026-2230610.0
Download of code without integrity check, inclusion of functionality from untrusted…
CVE-2026-472558.2
AgenticMail gives AI agents real email addresses and phone numbers. @agenticmail/api…
CVE-2026-489029.8
The password and username reset features created plain http links for https connections…
CVE-2026-240609.1
Service information is not encrypted when transmitted as BACnet packets over the wire,…

Frequently asked

Is CVE-2026-84381 being actively exploited?

CVE-2026-84381 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.11%.

How severe is CVE-2026-84381?

CVE-2026-84381 has a CVSS 3.1 base score of 8.1, rated high. EPSS estimates a 0.11% probability of exploitation.

How do I fix CVE-2026-84381?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-84381 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

See how prioritisation worksBook a demo

Get Patch this first every Monday

Five vulnerabilities that matter this week, ranked on real exploitation. Plain language, one email, no spam.

You can unsubscribe with one click from every issue. We handle your details as described in our privacy policy.

Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.