#VU80337 Incorrect Regular Expression in prism - CVE-2021-3801

Vulnerability identifier: #VU80337

Vulnerability risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-3801

CWE-ID: CWE-185

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
prism
Other software / Other software solutions

Vendor: PrismJS

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. A remote attacker can trick the victim into opening specially crafted data and perform regular expression denial of service (ReDos) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

prism: before 1.25.0

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External links
https://huntr.dev/bounties/8c16ab31-6eb6-46d1-b9a4-387222fe1b8a
https://github.com/prismjs/prism/commit/0ff371bb4775a131634f47d0fe85794c547232f9

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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.