Forge (also called node-forge) is a native implementation of Transport Layer Security in JavaScript. From 0.1.2 until 1.4.3, forge.http uses _trimString() in lib/http.js to remove trailing whitespace from response header values and cookie names and values with a regular expression that can take quadratic time. A malicious server or on-path attacker can supply a long whitespace run followed by a non-whitespace character in a response header, causing response.readHeader() or response.getCookies() to repeatedly scan the input and block the Node.js event loop or browser tab for minutes. Applications are affected only when they use forge.http with a socket pool to communicate with an untrusted server; forge.http is not loaded by require('node-forge'), and the issue has no confidentiality or integrity impact. This issue is fixed in version 1.4.3.