NetSight
medium5.3

CVE-2026-48125

UAParser.js is a JavaScript library to detect browsers, operating systems, CPUs, and devices from user-agent data.

Impact

UAParser.js is a JavaScript library to detect browsers, operating systems, CPUs, and devices from user-agent data. From 2.0.1 until 2.0.10, a regular expression denial-of-service vulnerability exists when using the Client Hints API. By sending a crafted Sec-CH-UA-Model header to an application that calls UAParser(headers).withClientHints(), an attacker can cause excessive CPU time due to catastrophic backtracking in the device regex because Client Hints values are copied without the UA_MAX_LENGTH limit used for User-Agent values. This issue is fixed in version 2.0.10.

Affected packages

EcosystemPackageAffectedFixed in
npmua-parser-js>= 2.0.1, < 2.0.102.0.10

Affected products

VendorProductAffected versions
Ua-Parser-Js ProjectUa-Parser-Js
from 2.0.1 before 2.0.10

Weakness classification

References