Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. Prior to 20.3.31, 21.2.23, and 22.1.6, the @angular/platform-server DOM emulation parser can enter an infinite synchronous loop when Angular server-side rendering processes attacker-controlled HTML containing an incomplete DOCTYPE that ends with whitespace at end of input. In Domino lib/HTMLParser.js, after_doctype_name_state emits doctype and EOF tokens without advancing nextchar or leaving the fixed-lookahead state, so the scanner repeatedly handles the same EOF marker. A remote unauthenticated attacker can use this condition through server-side HTML parsing paths such as innerHTML binding to consume a Node.js SSR worker at full CPU, starve the event loop, and stop concurrent and subsequent requests. This issue is fixed in versions 20.3.31, 21.2.23, and 22.1.6.
https://github.com/angular/domino/commit/4d97473116d000e3fd4d6f75ec98cbd67576fa6f
https://github.com/angular/angular/security/advisories/GHSA-f67j-2jqw-jpq7
https://github.com/angular/angular/releases/tag/v22.1.6
https://github.com/angular/angular/releases/tag/v21.2.23
https://github.com/angular/angular/releases/tag/v20.3.31
https://github.com/angular/angular/commit/fc2e8fbc0bda2f5c11585e8a0cbd88c074f5e567
https://github.com/angular/angular/commit/3db26e2544964d07a520836ad01f02f36ec88e25
Published: 2026-10-14
Updated: 2026-10-16
Base Score: 5
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P
Severity: Medium
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity: High
Base Score: 8.7
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.00716