Origin Validation Error Affecting undici package, versions >=7.0.0 <7.30.1>=8.0.0 <8.12.2
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-JS-UNDICI-21181009
- published18 Oct 2026
- disclosed15 Oct 2026
- creditKushal Khemka, Mayank Jangid, bengsky13
Introduced: 15 Oct 2026
NewCVE-2026-109829 (opens in a new tab)How to fix?
Upgrade undici to version 7.30.1, 8.12.2 or higher.
Overview
undici is an An HTTP/1.1 client, written from scratch for Node.js
Affected versions of this package are vulnerable to Origin Validation Error via cross-origin redirect handling in CacheHandler.onResponseStart, where a redirect to a different origin can cause the final response to be stored under the original (trusted) origin's cache key. An attacker who controls a redirect target can poison the shared cache by serving a response that gets keyed against a URL the application trusts, enabling subsequent cache-served responses to deliver attacker-controlled content. Additionally, intermediate redirect hops carrying restrictive Cache-Control directives (such as no-store or private) are not honored, allowing those hops to be laundered into a cacheable entry under the original key.
Note: This is only exploitable when an originless Agent, a shared MemoryCacheStore or SqliteCacheStore, and the composition compose(redirect(), cache()) are all used.