CVSS 3.1
9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCVE-2021-21322
Critical (9.8) in fastify-http-proxy project fastify-http-proxy. EPSS 1.6% chance of exploitation in the next 30 days. Fixed in fastify-http-proxy 4.3.1.
fastify-http-proxy is an npm package which is a fastify plugin for proxying your http requests to another server, with hooks. By crafting a specific URL, it is possible to escape the prefix of the proxied backend service. If the base url of the proxied server is `/pub/`, a user expect that accessing `/priv` on the target service would not be possible. In affected versions, it is possible. This is fixed in version 4.3.1.
Severity
- EPSS
- 1.6% chance of exploitation in the next 30 days; higher than 76% of CVEs (scores of 2026-10-31)
- CWE
- CWE-20
- Published
- Modified
- Record from
- the NVD, synced
Affected
- fastify-http-proxy_project:fastify-http-proxy
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-c4qr-gmr9-v23w | npm | fastify-http-proxy | <4.3.1 | 4.3.1 |
References
- https://github.com/fastify/fastify-http-proxy/commit/02d9b43c770aa16bc44470edecfaeb7c17985016
- https://github.com/fastify/fastify-http-proxy/security/advisories/GHSA-c4qr-gmr9-v23w
- https://www.npmjs.com/package/fastify-http-proxy
- https://github.com/fastify/fastify-http-proxy/commit/02d9b43c770aa16bc44470edecfaeb7c17985016
- https://github.com/fastify/fastify-http-proxy/security/advisories/GHSA-c4qr-gmr9-v23w