CVE-2026-85152 · GHSA-vp8m-p9jh-q5pm
undici vulnerable to cross-origin cache poisoning via missing origin isolation in interceptors
- Risk score
- 56/100
- CVSS
- 7.4 v3.1
- Exploit chance (30 days)
- 0.2%
- Published
- 29 Sep 2026
Open in the live forecast Today's forecast
What to know
- What it is
- When interceptors.cache() or interceptors.deduplicate() is used with a dispatcher that does not carry a single authoritative origin, or when a request supplies its own origin, undici builds the cache and deduplication keys without the actual destination origin. If a cache store or interceptor instance is shared across…
- Affected
- undici (npm) >= 8.10.0, < 8.10.2
- Fix
- Upgrade undici to 8.10.2 or later.
- Exploitation
- No known exploitation
Story map
At a glance
undici: Amber, patch this week. The undici WebSocket client throws an uncaught TypeError during the opening handshake when a server's 101 response includes a Sec-WebSocket-Protocol header that the client never requested. The throw occurs in a queueMicrotask callback with no surrounding try/catch, so it propagates as an uncaught exception and termina…
The flaws
- CVE-2026-85152: Undici vulnerable to cross-origin cache poisoning via missing origin isolation in interceptors (CVSS 7.4 · EPSS 0%)
- CVE-2026-19534: Undici vulnerable to Denial of Service via unrequested WebSocket subprotocol (CVSS 7.5 · EPSS 0%)
- CVE-2026-84961: Undici vulnerable to TLS certificate validation bypass via dropped connect options in BalancedPool (CVSS 7.4 · EPSS 0%)
- CVE-2026-84933: Undici vulnerable to cross-user cookie disclosure via Set-Cookie caching in shared caches (CVSS 6.5 · EPSS 0%)
The fix
Fix: Upgrade undici to 6.28.1 or 7.29.1 or 8.10.2 (whichever matches your release line) or later.
Who is exposed: undici (npm) >= 6.7.0, < 6.28.1; undici (npm) >= 7.0.0, < 7.29.1; undici (npm) >= 8.0.0, < 8.10.2
Where it stands
- No known exploitation
Connects to
- Same weakness: CWE-346 (CWE-346). 54 other warnings in 30 days
Why it is Yellow
- CVSS 7.4 high
- Remotely exploitable without logging in
- On your watchlist: npm
Affected packages
| Package | Ecosystem | Vulnerable | Fixed in |
|---|---|---|---|
| undici | npm | >= 8.10.0, < 8.10.2 | 8.10.2 |
References
- https://github.com/advisories/GHSA-vp8m-p9jh-q5pm
- https://github.com/nodejs/undici/security/advisories/GHSA-vp8m-p9jh-q5pm
- https://nvd.nist.gov/vuln/detail/CVE-2026-85152
- https://github.com/nodejs/undici/commit/caf6194d3dae989b731ed87ab85f182befe5eb80
- https://cna.openjsf.org/security-advisories.html
- https://github.com/nodejs/undici/releases/tag/v8.10.2
- https://github.com/advisories/GHSA-vp8m-p9jh-q5pm
Original description
## Impact When `interceptors.cache()` or `interceptors.deduplicate()` is used with a dispatcher that does not carry a single authoritative origin, or when a request supplies its own `origin`, undici builds the cache and deduplication keys without the actual destination origin. If a cache store or interceptor instance is shared across more than one origin, otherwise-identical requests to different origins are keyed together. An attacker who controls the response from one origin can then have that response returned for a request to a different, trusted origin when the method, path, and relevant headers match. This allows cross-origin information disclosure and persistent cache poisoning, including chains such as JWKS cache poisoning where a token signed with an attacker-held key is accepted as belonging to a trusted issuer. Applications that share `interceptors.cache()` or `interceptors.deduplicate()` state across origins are affected. An `Agent` is not affected, because its dispatch options include the request origin. This was introduced in undici 8.10.0 and affects 8.10.0 and 8.10.1. ## Patches Upgrade to undici v8.10.2. ## Workarounds Use a separate cache store and a separate interceptor instance for each origin, and do not share them across origins.
Last activity 29 Sep 2026. Patch Forecast updates every hour.