DEBIAN-CVE-2026-6734

Advisory lineage Upstream: 1 Downstream: 0
Upstream
CVE-2026-6734
Published: 17 Jun 2026, 18:18
Last modified:28 Jun 2026, 09:00

Vulnerability Summary

Overall Risk (default)
medium
35/100
CVSS Score
8.8 HIGH
3.1 (osv_debian)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

17 Jun 2026, 18:18
Published
Vulnerability first disclosed
28 Jun 2026, 09:00
Last Modified
Vulnerability information updated

Description

Impact: When using Socks5ProxyAgent, undici reuses a single connection pool across different origins without verifying that the pool's origin matches the requested origin. All requests are dispatched through the pool connected to the first origin, regardless of the intended destination. This causes cross-origin request routing: credentials and request data intended for origin B are sent to origin A, responses from the wrong origin are trusted, and HTTPS requests may be silently downgraded to HTTP. Impacted users are applications that use Socks5ProxyAgent (directly or via setGlobalDispatcher) and make requests to more than one origin. This was introduced in undici 7.23.0 via PR #4385 and affects all versions through 8.1.0. Patches: Upgrade to undici v7.26.0 or v8.2.0. Workarounds: Use a separate Socks5ProxyAgent instance per origin, or avoid using Socks5ProxyAgent with multiple origins.

CVSS Metrics

  • v3.1•HIGH•Score: 8.8CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Systems

  • debian•node-undici

    all | all | all | < 8.5.0+dfsg+~cs3.2.0-1

References (1)