In RC.1 some styles can’t be added using binding syntax

update (2.0.0 final)

import { Pipe, PipeTransform } from '@angular/core';
import { DomSanitizer } from '@angular/platform-browser';

@Pipe({name: 'safeHtml'})
export class SafeHtml implements PipeTransform {
  constructor(private sanitizer:DomSanitizer){}

  transform(html) {
    return this.sanitizer.bypassSecurityTrustStyle(html);
    // return this.sanitizer.bypassSecurityTrustHtml(html);
    // return this.sanitizer.bypassSecurityTrustScript(html);
    // return this.sanitizer.bypassSecurityTrustUrl(html);
    // return this.sanitizer.bypassSecurityTrustResourceUrl(html);
  }
}

See also https://angular.io/api/platform-browser/DomSanitizer

<div [innerHTML]="someHtml | safeHtml"

update

DomSanitizationService is going to be renamed to DomSanitizer in RC.6

original

This should be fixed in RC.2

See also Angular2 Developer Guide – Security


Angular2 intruduced sanitization of CSS values and property binding like [innerHTML]=... and [src]="..." in RC.1

See also https://github.com/angular/angular/issues/8491#issuecomment-217467582

The values can be marked as trusted by using DomSanitizer.bypassSecurityTrustStyle(...)

import {DomSanitizer} from '@angular/platform-browser';
...
constructor(sanitizer: DomSanitizationService) {
  this.backgroundImageStyle = sanitizer.bypassSecurityTrustStyle('url(' + this.image + ')');
  // for HTML
  // this.backgroundImageStyle = sanitizer.bypassSecurityTrustHtml(...);

}

and binding to this value instead the untrusted plain string.

This can also be wrapped in a pipe like

@Pipe({name: 'safeStyle'})
export class Safe {
  constructor(private sanitizer:Sanitizer){}

  transform(style) {
    return this.sanitizer.bypassSecurityTrustStyle(style);
    // return this.sanitizer.bypassSecurityTrustHtml(style);
    // return this.sanitizer.bypassSecurityTrustScript(value);
    // return this.sanitizer.bypassSecurityTrustUrl(value);
    // return this.sanitizer.bypassSecurityTrustResourceUrl(value);
  }
}
<div [ngStyle]="someStyle | safeStyle"></div>

with

someHtml = `<a href="#" onClick="alert(document.cookie);">click to see the awesome</a>`;

is still working though :-[ (it’s work in progress)

Plunker example (Angular 2.0.0-rc-1)

See also Angular 2 Security Tracking Issue

and https://angular.io/docs/ts/latest/api/platform-browser/index/DomSanitizer-class.html

Hint about {{...}}

Sanitized content can’t be bound using prop="{{sanitizedContent}}" because {{}} stringyfies the value before it is assigned which breaks sanitization.

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