CVE-2026-84933

undici's cache interceptor does not handle the Set-Cookie response header anywhere in its cache path, so it neither refuses to store nor strips that header. In shared cache mode, which is the default, an otherwise cacheable response that carries a Set-Cookie header, for example one marked with a public and max-age directive, is stored and then re-served to a later caller that matches the same cache key. As a result one caller's cookie is disclosed to a different caller, and an untrusted server can inject cookies into cached responses served to all subsequent callers. This violates the requirement that a shared cache must not store cookies. This affects undici versions from 7.0.0 up to 7.29.1 and from 8.0.0 up to 8.10.2. Users should upgrade to undici 7.29.1 or 8.10.2.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://cna.openjsf.org/security-advisories.html	Third Party Advisory
https://github.com/nodejs/undici/security/advisories/GHSA-2jfj-6hjv-fm6j	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-09-04 17:17

Updated : 2026-09-15 14:38

NVD link : CVE-2026-84933

Mitre link : CVE-2026-84933

CVE.ORG link : CVE-2026-84933

JSON object : View

Products Affected

nodejs

undici

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

CWE-524

Use of Cache Containing Sensitive Information

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