---
id: CVE-2026-109829
title: undici is an HTTP client library for Node.js
summary: >-
  undici is an HTTP client library for Node.js. In versions 7.0.0 through 7.30.0
  and 8.0.0 through 8.12.1, when an originless Agent composes the redirect and
  cache interceptors in that order with a shared cache store, the cache builds
  its …
severity: high
cvss: 7.4
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N'
cwe:
  - CWE-346
  - CWE-524
vendor: undici
product: undici
affected:
  - undici >= 7.0.0 < 7.30.1
  - undici >= 8.0.0 < 8.12.2
published: '2026-10-15'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T19:17:21.513'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-109829'
references:
  - url: 'https://cna.openjsf.org/security-advisories.html'
    label: ce714d77-add3-4f53-aff5-83d477b104bb
  - url: 'https://github.com/nodejs/undici/security/advisories/GHSA-4w7w-5xrc-9h26'
    label: ce714d77-add3-4f53-aff5-83d477b104bb
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-109829.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-109829'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2553679'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-109829'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-109829'
  - url: 'https://github.com/nodejs/undici/commit/26c2bfb3def0'
  - url: 'https://access.redhat.com/errata/RHSA-2026:84706'
  - url: 'https://access.redhat.com/errata/RHSA-2026:84657'
  - url: >-
      https://github.com/nodejs/undici/commit/26c2bfb3def0b67241ce878e80657ed5d6c3efa8
  - url: >-
      https://github.com/nodejs/undici/commit/b20b82ad80a405a12b6ce1f341bcd418de390aa0
  - url: 'https://github.com/nodejs/undici/releases/tag/v7.30.1'
  - url: 'https://github.com/nodejs/undici/releases/tag/v8.12.2'
  - url: 'https://github.com/advisories/GHSA-4w7w-5xrc-9h26'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
  - ghsa
  - npm
ingestedAt: '2026-10-15T19:25:46.400Z'
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-16T20:03:57.700768Z'
epss: 0.00149
epssPercentile: 0.04114
patched:
  - hardened_images
aliases:
  - GHSA-4w7w-5xrc-9h26
ecosystem: npm
---

## Overview

undici is an HTTP client library for Node.js. In versions 7.0.0 through 7.30.0 and 8.0.0 through 8.12.1, when an originless Agent composes the redirect and cache interceptors in that order with a shared cache store, the cache builds its key from the original request URL before the redirect handler changes the origin, so a response produced after a cross-origin redirect is stored under the original key. An attacker who controls the target of a redirect from a trusted URL can have their response cached under that trusted URL and served to later callers, allowing persistent cache poisoning, and the same key confusion lets a private, non-stored redirect response to a user-specific resource be stored under the original URL and served to a later unauthenticated caller, disclosing private data. Applications are affected only when an originless Agent, a shared cache store, and the redirect-then-cache composition are all used. The issue is fixed in undici 7.30.1 and 8.12.2, which verify the producing origin still matches the cache key and preserve each redirect hop's cache-control policy before storing, and users should upgrade to one of those versions or later. As a workaround, compose the cache interceptor before the redirect interceptor, use per-origin dispatchers and cache stores, or disable shared caching on redirect-capable requests.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Important · affected: Exploit Intelligence, Red Hat AMQ Broker 7, Red Hat Ansible Automation Platform 2, Red Hat Build of Podman Desktop, Red Hat Developer Hub, Red Hat Enterprise Linux 10, … · no fix planned: Red Hat Hardened Images, Secrets Management Console for Red Hat OpenShift, Exploit Intelligence, Red Hat AMQ Broker 7, … · updated 2026-10-20 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-109829.json)
- **RHSA-2026:84706** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-10-19 · [advisory](https://access.redhat.com/errata/RHSA-2026:84706)
- **RHSA-2026:84657** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-10-19 · [advisory](https://access.redhat.com/errata/RHSA-2026:84657)

## Package advisory (CVE-2026-109829)

Affected packages:

- `undici >= 7.0.0, < 7.30.1`
- `undici >= 8.0.0, < 8.12.2`

Patched in:

- `undici 7.30.1`
- `undici 8.12.2`

Source: https://github.com/advisories/GHSA-4w7w-5xrc-9h26