5.9
MEDIUM CVSS 3.1
CVE-2026-14643
undici vulnerable to cross-user information disclosure via whitespace around equals in Cache-Control directives
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.

INFO

Published Date :

July 29, 2026, 10:16 p.m.

Last Modified :

July 29, 2026, 10:16 p.m.

Remotely Exploit :

Yes !

Source :

ce714d77-add3-4f53-aff5-83d477b104bb
Affected Products

The following products are affected by CVE-2026-14643 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM ce714d77-add3-4f53-aff5-83d477b104bb
CVSS 3.1 MEDIUM MITRE-CVE
Solution
Update undici to patch cache handling issues related to Cache-Control directives.
  • Update undici to version 7.29.0 or later.
  • Update undici to version 8.9.0 or later.
  • Ensure Cache-Control directives are parsed correctly.
  • Validate cache behavior in shared mode.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-14643.

URL Resource
https://cna.openjsf.org/security-advisories.html
https://github.com/nodejs/undici/security/advisories/GHSA-jr45-8vmc-qm54
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-14643 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-14643 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-14643 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-14643 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by ce714d77-add3-4f53-aff5-83d477b104bb

    Jul. 29, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'undici', 'product': 'undici', 'versions': [{'status': 'affected', 'version': '7.0.0', 'lessThan': '7.29.0', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '7.29.0', 'versionType': 'semver'}, {'status': 'affected', 'version': '8.0.0', 'lessThan': '8.9.0', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '8.9.0', 'versionType': 'semver'}], 'packageURL': 'pkg:npm/undici', 'defaultStatus': 'unaffected'}]
    Added 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.
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
    Added CWE CWE-436
    Added CWE CWE-524
    Added Reference https://cna.openjsf.org/security-advisories.html
    Added Reference https://github.com/nodejs/undici/security/advisories/GHSA-jr45-8vmc-qm54
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.