Description
is.js is a general-purpose check library. Versions 0.9.0 and prior contain one or more regular expressions that are vulnerable to Regular Expression Denial of Service (ReDoS). is.js uses a regex copy-pasted from a gist to validate URLs. Trying to validate a malicious string can cause the regex to loop “forever." This vulnerability was found using a CodeQL query which identifies inefficient regular expressions. is.js has no patch for this issue.
References (2)
Core 2
Core References
Issue Tracking, Third Party Advisory
https://github.com/arasatasaygin/is.js/issues/320
Exploit, Third Party Advisory
https://securitylab.github.com/advisories/GHSL-2020-295-redos-is.js
Scores
CVSS v3
7.5
EPSS
0.0027
EPSS Percentile
50.6%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-1333
CWE-400
Status
published
Products (2)
is.js_project/is.js
< 0.9.0
npm/is_js
0npm
Published
Dec 22, 2022
Tracked Since
Feb 18, 2026