#VU59234 Inconsistent interpretation of HTTP requests in llhttp - CVE-2021-22960

Vulnerability identifier: #VU59234

Vulnerability risk: Medium

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-22960

CWE-ID: CWE-444

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
llhttp
Web applications / Modules and components for CMS

Vendor: Node.js Foundation

Description

The vulnerability allows a remote attacker to preform HTTP request smuggling attacks.

The vulnerability exists due to improper validation of HTTP requests, where the application ignores chunk extensions when parsing the body of chunked requests. A remote attacker can send a specially crafted HTTP request to the server and smuggle arbitrary HTTP headers.

Successful exploitation of vulnerability may allow an attacker to poison HTTP cache and perform phishing attacks.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

llhttp: 1.0.1, 1.1.0 - 1.1.4, 2.0.0 - 2.0.5, 2.1.0 - 2.1.3, 2.2.0 - 2.2.1, 3.0.0 - 3.0.1, 4.0.0, 4.1.0 - 4.1.1, 5.0.0, 5.1.0, 6.0.0 - 6.0.5

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External links
https://hackerone.com/reports/1238099

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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.