CVE-2021-21322

Prefix escape

Description

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.

Category

10.0
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.60%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory npmjs.com
Affected: fastify fastify-http-proxy
Published at:
Updated at:

References

Link Tags
https://github.com/fastify/fastify-http-proxy/security/advisories/GHSA-c4qr-gmr9-v23w third party advisory
https://www.npmjs.com/package/fastify-http-proxy third party advisory product
https://github.com/fastify/fastify-http-proxy/commit/02d9b43c770aa16bc44470edecfaeb7c17985016 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-21322?
CVE-2021-21322 has been scored as a critical severity vulnerability.
How to fix CVE-2021-21322?
To fix CVE-2021-21322, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-21322 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-21322 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21322?
CVE-2021-21322 affects fastify fastify-http-proxy.
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