undici vulnerable to cache poisoning and cross-user disclosure via cross-origin redirects
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.
CVE-2026-109829
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-109829
undici
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "undici",
"product": "undici",
"versions": [
{
"status": "affected",
"version": "7.0.0",
"lessThan": "7.30.1",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "7.30.1",
"versionType": "semver"
},
{
"status": "affected",
"version": "8.0.0",
"lessThan": "8.12.2",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "8.12.2",
"versionType": "semver"
}
],
"packageURL": "pkg:npm/undici",
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-109829
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #34420 · Revision 1
- Added to Heist Feed
- Publisher date