MEDIUM · 5.9

CVE-2026-14643

undici's cache interceptor mishandles optional whitespace placed around the equals sign of a qualified no-cache or private Cache-Control directive. In undici from 7.0.0 up to before 7.29.0 and from 8....

Vulnerability Description

undici's cache interceptor mishandles optional whitespace placed around the equals sign of a qualified no-cache or private Cache-Control directive. In undici from 7.0.0 up to before 7.29.0 and from 8.0.0 up to before 8.9.0, the parser either drops the directive or stores a field name with literal quote characters, so the cache decision fails to recognize the qualification and the response is stored. In shared-cache mode, this lets a response containing one user's authenticated data be served from cache to a later caller, including an unauthenticated one, when both requests resolve to the same cache key. It affects applications that enable the cache interceptor in shared mode, forward Authorization headers upstream, and receive cacheable responses with qualified directives padded with whitespace around the equals sign. This is the whitespace-around-equals variant that the fix for CVE-2026-9678 did not normalize, and it is fixed in undici 7.29.0 and 8.9.0.

CVSS Score

5.9

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE

Affected Products

VendorProductVersions
NodejsUndici>= 7.0.0, < 7.29.0

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-14643?

CVE-2026-14643 is a vulnerability with a CVSS score of 5.9 (MEDIUM). undici's cache interceptor mishandles optional whitespace placed around the equals sign of a qualified no-cache or private Cache-Control directive. In undici from 7.0.0 up to before 7.29.0 and from 8....

How severe is CVE-2026-14643?

CVE-2026-14643 has been rated MEDIUM with a CVSS base score of 5.9/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-14643?

Check the references section above for vendor advisories and patch information. Affected products include: Nodejs Undici.