#VU76184 Incorrect regular expression in css-what - CVE-2022-21222

Vulnerability identifier: #VU76184

Vulnerability risk: Medium

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

CVE-ID: CVE-2022-21222

CWE-ID: CWE-185

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
css-what
Web applications / JS libraries

Vendor: fb55

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient input validation when processing regular expressions in the re_attr variable of index.js. A remote attacker can pass specially crafted data to the application and perform regular expression denial of service (ReDos) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

css-what: 2.0.0 - 2.1.2

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External links
https://security.snyk.io/vuln/SNYK-JS-CSSWHAT-3035488
https://github.com/fb55/css-what/blob/a38effd5a8f5506d75c7f8f13cbd8c76248a3860/index.js%23L12
https://lists.debian.org/debian-lts-announce/2023/03/msg00001.html

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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.