CVE-2026-48125 | UAParser.js is a JavaScript library to detect browsers, oper… | CVSS 5.3 MEDIUM

Description

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.

Metadata

CVE ID: CVE-2026-48125
State: PUBLISHED
Assigner: GitHub_M
Reserved: 2026-05-20 18:46 UTC
Published: 2026-07-14 20:54 UTC
Last updated: 2026-07-14 20:54 UTC
Primary CWE: CWE-400
CWE-400: Uncontrolled Resource Consumption
Vendor / Product: faisalman / ua-parser-js
Sources: cve.org · NVD

Severity & Metrics

5.3 MEDIUM CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected products (1)

Vendor	Product	Platform	Versions
faisalman	ua-parser-js	—	>= 2.0.1, < 2.0.10

Weakness (CWE)

CWE	Source	Description
CWE-1333	cna	CWE-1333: Inefficient Regular Expression Complexity
CWE-400	cna	CWE-400: Uncontrolled Resource Consumption

CVSS scores (1)

Score	Severity	Version	Source	Vector
5.3	MEDIUM	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

References (3)

https://github.com/faisalman/ua-parser-js/security/advisories/GHSA-9h5v-pfqq-x599 https://github.com/faisalman/ua-parser-js/security/advisories/GHSA-9h5v-pfqq-x599
https://github.com/faisalman/ua-parser-js/commit/90354d3458495628b1d3ba68a9d76673e6d14fc5 https://github.com/faisalman/ua-parser-js/commit/90354d3458495628b1d3ba68a9d76673e6d14fc5
https://github.com/faisalman/ua-parser-js/releases/tag/2.0.10 https://github.com/faisalman/ua-parser-js/releases/tag/2.0.10