Node.js undici up to 7.28.9/8.8.9 Cache Interceptor improper authorization

Summaryinfo

A vulnerability identified as problematic has been detected in Node.js undici up to 7.28.9/8.8.9. Affected is an unknown function of the component Cache Interceptor. This manipulation causes improper authorization. This vulnerability is registered as CVE-2026-14643. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability has been found in Node.js undici up to 7.28.9/8.8.9 and classified as problematic. Affected by this vulnerability is some unknown functionality of the component Cache Interceptor. The manipulation with an unknown input leads to a improper authorization vulnerability. The CWE definition for the vulnerability is CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality. The summary by CVE is:

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.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-14643 since 07/03/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1548.002 according to MITRE ATT&CK.

Upgrading to version 7.29.0 or 8.9.0 eliminates this vulnerability.

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Productinfo

Type

• JavaScript Library

Vendor

• Node.js

Name

• undici

Version

• 7.28.0
• 7.28.1
• 7.28.2
• 7.28.3
• 7.28.4
• 7.28.5
• 7.28.6
• 7.28.7
• 7.28.8
• 7.28.9
• 8.8.0
• 8.8.1
• 8.8.2
• 8.8.3
• 8.8.4
• 8.8.5
• 8.8.6
• 8.8.7
• 8.8.8
• 8.8.9

License

• open-source

CPE 2.3info

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• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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