CVE-2021-3801: Inefficient Regular Expression Complexity in prismjs/prism

Published Sep 11, 2021
·
Updated

Insufficient Regular Expression Complexity in prismjs leads to a Regular Expression Denial of Service (ReDoS) attack. An unauthenticated attacker can exploit this flaw to cause an application to consume an excess amount of CPU by providing a crafted HTML comment as input. This can result in a denial of service attack.

Affected Software

2 affected componentsFixes available
redhat/prismjs<1.25.0
1.25.0
PrismJS Prism Node.js<1.25.0

Event History

Sep 11, 2021
CVE Published
12:00 AM
Data Sourced
12:00 AM
RemedyDescriptionSeverityWeaknessAffected Software
Sep 15, 2021
CVE Published
via MITRE·12:40 PM
Data Sourced
via MITRE·12:40 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is CVE-2021-3801?

CVE-2021-3801 is a vulnerability in prismjs that allows an unauthenticated attacker to cause a denial of service (DoS) attack by exploiting insufficient regular expression complexity.

2

How does CVE-2021-3801 work?

CVE-2021-3801 works by allowing an attacker to provide a crafted HTML comment as input, causing an application to consume excessive amounts of CPU resources.

3

What is the severity of CVE-2021-3801?

The severity of CVE-2021-3801 is rated as high, with a CVSS score of 6.5.

4

What is the affected software of CVE-2021-3801?

The affected software of CVE-2021-3801 includes Prismjs versions up to exclusive 1.25.0 and Node.js version in the CPE 'cpe:2.3:a:prismjs:prism:*:*:*:*:*:node.js:*:*' up to exclusive 1.25.0.

5

How can CVE-2021-3801 be remediated?

To remediate CVE-2021-3801, it is recommended to update Prismjs to version 1.25.0 or higher.

Contact

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