#VU87847 Path traversal in fasthttp - CVE-2022-21221

Vulnerability identifier: #VU87847

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2022-21221

CWE-ID: CWE-22

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
fasthttp
Universal components / Libraries / Programming Languages & Components

Vendor: valyala

Description

The vulnerability allows a remote attacker to perform directory traversal attacks.

The vulnerability exists due to insufficient sanitization of user-supplied passed via the ServeFile function. A remote attacker can use a backslash %5c character in the path and read contents of arbitrary files on the system.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability..

Vulnerable software versions

fasthttp: 0.1.0 - 1.33.0

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External links
https://github.com/valyala/fasthttp/commit/15262ecf3c602364639d465daba1e7f3604d00e8
https://github.com/valyala/fasthttp/issues/1226
https://github.com/valyala/fasthttp/commit/6b5bc7bb304975147b4af68df54ac214ed2554c1
https://github.com/valyala/fasthttp/releases/tag/v1.34.0
https://snyk.io/vuln/SNYK-GOLANG-GITHUBCOMVALYALAFASTHTTP-2407866

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.