CVE-2026-69149

About vulnerability

A Cross-Site Scripting (XSS) vulnerability exists in @angular/platform-server’s DOM emulation dependency (domino) when serializing the content of fallback raw-content elements (<iframe>, <noembed>, <noframes>, and <noscript>).

When rendering dynamic text content inside fallback raw-content elements via template bindings, the template engine expects the browser to render the content safely. Under Server-Side Rendering (SSR), domino is configured with scripting enabled, meaning these elements are treated as raw-text elements.

However, domino’s serializer previously did not escape text nodes within fallback raw-content elements (<iframe>, <noembed>, <noframes>, <noscript>) during DOM serialization. As a result, any occurrence of closing tags in the bound dynamic text was not escaped.

The unescaped closing tag could be serialized directly into the output HTML. When parsed by a browser or re-parsed during SSR post-processing without preserving raw-content parser state, an injected closing tag closes the element early, allowing an injected script block to execute in the user’s browser context, causing same-origin Cross-Site Scripting (XSS).

Impact

This vulnerability allows an attacker to perform same-origin Cross-Site Scripting (XSS) attacks against any user visiting an SSR-rendered page that binds user-controlled data inside fallback raw-content elements (<iframe>, <noembed>, <noframes>, <noscript>). This can lead to session hijacking, credentials theft, unauthorized actions on behalf of users, and defacement.

Patched Versions

• 22.0.7
• 21.2.19
• 20.3.27

Workarounds

If you cannot immediately update your dependencies, you can mitigate this issue using any of the following approaches:

• Disable critical CSS inlining: Critical CSS inlining in Angular SSR post-processes the rendered HTML using domino. Disabling this step prevents domino from re-parsing and re-serializing the HTML during server-side rendering.
• In angular.json, set inlineCritical to false under style optimization options:

{
"projects": {
"my-app": {
"architect": {
"build": {
"builder": "@angular/build:application",
"options": {
"optimization": {
"styles": {
"inlineCritical": false
}
}
}
}
}
}
}
}

• When rendering programmatically with CommonEngine, set inlineCriticalCss: false in your render options.
• Avoid binding user-controlled values inside fallback raw-content elements (<iframe>, <noembed>, <noframes>, <noscript>).
• Sanitize user input placed inside these elements to explicitly strip or escape closing tags before passing it to the template.

Affected product:

AngularJS , angular-animations , angular-build , angular-common , angular-compiler , angular-compiler-cli , angular-core , angular-create , angular-devkit-build-angular , angular-devkit-core , angular-devkit-schematics-cli , angular-elements , angular-estree-parser , angular-forms , angular-localize , angular-platform-browser , angular-platform-browser-dynamic , angular-platform-server , angular-pwa , angular-router , angular-service-worker , angular-ssr , angular-upgrade , create-storybook , domino , ng-packagr , ngtools-webpack , nguniversal , sb , schematics-angular , sentry-angular , sentry-astro , sentry-deno , sentry-ember , sentry-gatsby , sentry-javascript , sentry-replay , sentry-wasm , storybook , storybook-addon-a11y , storybook-addon-actions , storybook-addon-backgrounds , storybook-addon-controls , storybook-addon-docs , storybook-addon-essentials , storybook-addon-highlight , storybook-addon-interactions , storybook-addon-jest , storybook-addon-links , storybook-addon-mdx-gfm , storybook-addon-measure , storybook-addon-onboarding , storybook-addon-outline , storybook-addon-storysource , storybook-addon-themes , storybook-addon-toolbars , storybook-addon-viewport , storybook-angular , storybook-blocks , storybook-builder-manager , storybook-builder-vite , storybook-builder-webpack5 , storybook-channels , storybook-cli , storybook-client-logger , storybook-codemod , storybook-components , storybook-core , storybook-core-common , storybook-core-events , storybook-core-server , storybook-core-webpack , storybook-csf-plugin , storybook-csf-tools , storybook-docs-tools , storybook-ember , storybook-experimental-addon-test , storybook-experimental-nextjs-vite , storybook-html , storybook-html-vite , storybook-html-webpack5 , storybook-instrumenter , storybook-manager , storybook-manager-api , storybook-nextjs , storybook-node-logger , storybook-preact , storybook-preact-vite , storybook-preact-webpack5 , storybook-preset-create-react-app , storybook-preset-html-webpack , storybook-preset-preact-webpack , storybook-preset-react-webpack , storybook-preset-server-webpack , storybook-preset-svelte-webpack , storybook-preset-vue3-webpack , storybook-preview , storybook-preview-api , storybook-react , storybook-react-dom-shim , storybook-react-native-web-vite , storybook-react-vite , storybook-react-webpack5 , storybook-router , storybook-server , storybook-server-webpack5 , storybook-source-loader , storybook-svelte , storybook-svelte-vite , storybook-svelte-webpack5 , storybook-sveltekit , storybook-telemetry , storybook-test , storybook-theming , storybook-types , storybook-vue3 , storybook-vue3-vite , storybook-vue3-webpack5 , storybook-web-components , storybook-web-components-vite , storybook-web-components-webpack5

Affected packages:

@angular/animations @ 17.3.12 (+3038 more)