CVE-2022-21221 Directory Traversal
Attackers can read arbitrary files on Windows systems via directory traversal in the fasthttp library's ServeFile function.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2022-21221?
CVE-2022-21221 is a medium-severity path traversal vulnerability in github.com/valyala/fasthttp, published on 17 Mar 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The package github.com/valyala/fasthttp before 1.34.0 are vulnerable to Directory Traversal via the ServeFile function, due to improper sanitization. It is possible to be exploited by using a backslash %5c character in the path. **Note:** This security issue impacts Windows users only.
Weakness: CWE-22
Which versions are affected by CVE-2022-21221?
3 open source packages ship an affected version, including github.com/valyala/fasthttp. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/valyala/fasthttp Go | All versions | 1.34.0 |
github.com/valyala/fasthttp Go | All versions | 1.34.0 |
github.com/valyala/fasthttp Go | All versions | 1.34.0 |
Products include Fasthttp Project Fasthttp.
How do I fix CVE-2022-21221?
Upgrade github.com/valyala/fasthttp to 1.34.0 or later.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2022-21221 being exploited?
There is no known exploitation of CVE-2022-21221 in the wild and no public exploit code.
Sources
Also known as GHSA-fx95-883v-4q4h, GO-2022-0355, SNYK-GOLANG-GITHUBCOMVALYALAFASTHTTP-2407866.