---
id: CVE-2026-84933
title: >-
  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
summary: >-
  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…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N'
cwe:
  - CWE-200
  - CWE-524
vendor: nodejs
product: undici
affected:
  - 'undici >= 7.0.0, < 7.29.1'
  - 'undici >= 8.0.0, < 8.10.2'
patched:
  - undici 8.10.2
published: '2026-09-04'
updated: '2026-09-15'
sourceUpdated: '2026-09-15T14:38:55.600'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-84933'
references:
  - url: 'https://cna.openjsf.org/security-advisories.html'
    label: ce714d77-add3-4f53-aff5-83d477b104bb
  - url: 'https://github.com/nodejs/undici/security/advisories/GHSA-2jfj-6hjv-fm6j'
    label: ce714d77-add3-4f53-aff5-83d477b104bb
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-84933.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-84933'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2528756'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-84933'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-84933'
  - url: 'https://access.redhat.com/errata/RHSA-2026:66008'
  - url: 'https://access.redhat.com/errata/RHSA-2026:54438'
  - url: 'https://access.redhat.com/errata/RHSA-2026:54389'
tags:
  - nvd
  - csaf
  - vex
  - red-hat
epss: 0.00337
epssPercentile: 0.244
ingestedAt: '2026-09-08T19:08:49.593Z'
---

## Overview

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.

## Affected

- `undici >= 7.0.0, < 7.29.1`
- `undici >= 8.0.0, < 8.10.2`

## Remediation

Upgrade past the affected range:

- `undici 8.10.2`

## Vendor advisories

- **RHSA-2026:66008** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-09-09 · [advisory](https://access.redhat.com/errata/RHSA-2026:66008)
- **RHSA-2026:54438** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-08-12 · [advisory](https://access.redhat.com/errata/RHSA-2026:54438)
- **RHSA-2026:54389** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-08-12 · [advisory](https://access.redhat.com/errata/RHSA-2026:54389)
- **Red Hat VEX** · Moderate · affected: OpenShift Pipelines, Red Hat Build of Podman Desktop, Red Hat Developer Hub, Red Hat Enterprise Linux 10, Red Hat Hardened Images, Red Hat OpenShift AI (RHOAI), … · no fix planned: Red Hat Trusted Artifact Signer, Red Hat Hardened Images, OpenShift Pipelines, Red Hat Build of Podman Desktop, … · updated 2026-09-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-84933.json)