CVE-2026-6733

Impact: Undici's HTTP/1.1 client is vulnerable to response queue poisoning on reused keep-alive sockets. An attacker-controlled upstream server can inject an unsolicited HTTP/1.1 response onto an idle socket after a request completes. When the client dispatches the next request on that socket, it associates the injected response with the new request, causing responses to be delivered to the wrong requests. This requires an attacker-controlled or compromised upstream HTTP/1.1 server and keep-alive connection reuse. Patches: Upgrade to undici v6.26.0, v7.28.0 or v8.5.0. Workarounds: Disable keep-alive connection reuse by setting keepAliveTimeout: 0 on the Client or Pool.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://cna.openjsf.org/security-advisories.html	Vendor Advisory
https://github.com/nodejs/undici/security/advisories/GHSA-35p6-xmwp-9g52	Mitigation Vendor Advisory
https://hackerone.com/reports/3582376	Issue Tracking

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:nodejs:undici::::::node.js::*
	cpe:2.3:a:nodejs:undici::::::node.js::*
	cpe:2.3:a:nodejs:undici::::::node.js::*

History

27 Jun 2026, 23:46

Type	Values Removed	Values Added
CPE		cpe:2.3:a:nodejs:undici::::::node.js::*
First Time		Nodejs Nodejs undici
References	~~() https://cna.openjsf.org/security-advisories.html -~~	() https://cna.openjsf.org/security-advisories.html - Vendor Advisory
References	~~() https://github.com/nodejs/undici/security/advisories/GHSA-35p6-xmwp-9g52 -~~	() https://github.com/nodejs/undici/security/advisories/GHSA-35p6-xmwp-9g52 - Mitigation, Vendor Advisory
References	~~() https://hackerone.com/reports/3582376 -~~	() https://hackerone.com/reports/3582376 - Issue Tracking

17 Jun 2026, 20:20

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-17 18:18

Updated : 2026-06-27 23:46

NVD link : CVE-2026-6733

Mitre link : CVE-2026-6733

CVE.ORG link : CVE-2026-6733

JSON object : View

Products Affected

nodejs

undici

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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