Advisories for Npm/@Angular/Core package

2026

Angular: Template and Attribute Namespace Sanitization Bypass (XSS)

An issue in the @angular/compiler and @angular/core packages allows bypassing element and attribute sanitization/validation through specific namespace workarounds. Specifically, namespaced script elements (e.g., <svg:script> or <:svg:script>) were not properly identified as script elements by the Angular template preparser, allowing them to pass through template compilation without being stripped. Furthermore, security context schema mappings for element attributes did not consistently handle attributes within namespaced elements (like SVG and MathML), opening up …

Angular Client Hydration DOM Clobbering & Response-Cache Poisoning

To optimize client-side bootstrap in Server-Side Rendered (SSR) environments, Angular supports Hydration via provideClientHydration(). During SSR, Angular serializes the application's runtime state (such as cached HttpClient responses) and outputs it into the HTML stream as a <script> tag with a predictable identifier: <script type="application/json" id="ng-state"> {"some-api-url": {"body": …}} </script> During client bootstrap, Angular recovers this state by looking up the element via document.getElementById('ng-state') and parsing its text content. Because the …

@angular/core: Angular Template and Dynamic Component Namespace Bypass leading to Cross-Site Scripting (XSS)

An issue in the @angular/core package allows bypassing script-execution restrictions during dynamic component creation. Specifically, the dynamic component instantiation mechanism (createComponent) failed to reject mounting components directly onto a <script> or namespaced script element (such as <svg:script>). This enabled the initialization of custom components on a tag that executes scripts, allowing attackers to hijack or inject script-executing hosts. This flaw enables an attacker who can control the host element or …

Angular vulnerable to XSS in i18n attribute bindings

A Cross-Site Scripting (XSS) vulnerability has been identified in the Angular runtime and compiler. It occurs when the application uses a security-sensitive attribute (for example href on an anchor tag) together with Angular's ability to internationalize attributes. Enabling internationalization for the sensitive attribute by adding i18n-<attribute> name bypasses Angular's built-in sanitization mechanism, which when combined with a data binding to untrusted user-generated data can allow an attacker to inject a …

Angular i18n vulnerable to Cross-Site Scripting

A Cross-site Scripting (XSS) vulnerability has been identified in the Angular internationalization (i18n) pipeline. In ICU messages (International Components for Unicode), HTML from translated content was not properly sanitized and could execute arbitrary JavaScript. Angular i18n typically involves three steps, extracting all messages from an application in the source language, sending the messages to be translated, and then merging their translations back into the final source code. Translations are frequently …

Angular has XSS Vulnerability via Unsanitized SVG Script Attributes

A Cross-Site Scripting (XSS) vulnerability has been identified in the Angular Template Compiler. The vulnerability exists because Angular’s internal sanitization schema fails to recognize the href and xlink:href attributes of SVG <script> elements as a Resource URL context. In a standard security model, attributes that can load and execute code (like a script's source) should be strictly validated. However, because the compiler does not classify these specific SVG attributes correctly, …

2022

Angular vulnerable to Cross-site Scripting

A vulnerability was found in Angular up to 11.0.4/11.1.0-next.2. It has been classified as problematic. Affected is the handling of comments. The manipulation leads to cross site scripting. It is possible to launch the attack remotely but it might require an authentication first. Upgrading to version 10.2.5, 11.0.5 or 11.1.0-next.3 is advised to to address this issue.