Useragent is a user agent parser for Node.js. All versions as of time of publication contain one or more regular expressions that are vulnerable to Regular Expression Denial of Service (ReDoS). As of time of publication, no patches are available.

Auth. (admin+) Stored Cross-Site Scripting (XSS) vulnerability in Fernando Briano UserAgent-Spy plugin <= 1.3.1 versions.

Yet Another UserAgent Analyzer (Yauaa) is a java library that tries to parse and analyze the useragent string and extract as many relevant attributes as possible. Applications using the Client Hints analysis feature introduced with 7.0.0 can crash because the Yauaa library throws an ArrayIndexOutOfBoundsException. If uncaught the exception will result in a program crash. Applications that do not use this feature are not affected. Users are advised to upgrade to version 7.9.0. Users unable to upgrade may catch and discard any ArrayIndexOutOfBoundsException thrown by the Yauaa library.

Useragent is used to parse useragent headers. It uses several regular expressions to accomplish this. An attacker could edit their own headers, creating an arbitrarily long useragent string, causing the event loop and server to block. This affects Useragent 2.1.12 and earlier.