GHSA-5cp4-xmrw-59wf: Angular Cross-Site Scripting Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-5cp4-xmrw-59wf",
  "modified" : "2021-10-08T21:25:58Z",
  "published" : "2020-08-05T21:47:02Z",
  "aliases" : [ ],
  "summary" : "XSS via JQLite DOM manipulation functions in AngularJS",
  "details" : "### Summary\nXSS may be triggered in AngularJS applications that sanitize user-controlled HTML snippets before passing them to `JQLite` methods like `JQLite.prepend`, `JQLite.after`, `JQLite.append`, `JQLite.replaceWith`, `JQLite.append`, `new JQLite` and `angular.element`.\n\n### Description\n\nJQLite (DOM manipulation library that's part of AngularJS) manipulates input HTML before inserting it to the DOM in `jqLiteBuildFragment`.\n\nOne of the modifications performed [expands an XHTML self-closing tag](https://github.com/angular/angular.js/blob/418355f1cf9a9a9827ae81d257966e6acfb5623a/src/jqLite.js#L218).\n\nIf `jqLiteBuildFragment` is called (e.g. via `new JQLite(aString)`) with user-controlled HTML string that was sanitized (e.g. with [DOMPurify](https://github.com/cure53/DOMPurify)), the transformation done by JQLite may modify some forms of an inert, sanitized payload into a payload containing JavaScript - and trigger an XSS when the payload is inserted into DOM.\n\nThis is similar to a bug in jQuery `htmlPrefilter` function that was [fixed in 3.5.0](https://blog.jquery.com/2020/04/10/jquery-3-5-0-released/).\n\n### Proof of concept\n\n```javascript\nconst inertPayload = `<div><style><style/><img src=x onerror=\"alert(1337)\"/>` \n```\nNote that the style element is not closed and `<img` would be a text node inside the style if inserted into the DOM as-is.\nAs such, some HTML sanitizers would leave the `<img` as is without processing it and stripping the `onerror` attribute.\n\n```javascript\nangular.element(document).append(inertPayload);\n```\nThis will alert, as `<style/>` will be replaced with `<style></style>` before adding it to the DOM, closing the style element early and reactivating `img`.\n\n### Patches\nThe issue is patched in `JQLite` bundled with angular 1.8.0. AngularJS users using JQuery should upgrade JQuery to 3.5.0, as a similar vulnerability [affects jQuery <3.5.0](https://github.com/jquery/jquery/security/advisories/GHSA-gxr4-xjj5-5px2).\n\n### Workarounds\nChanging sanitizer configuration not to allow certain tag grouping (e.g. `<option><style></option>`) or inline style elements may stop certain exploitation vectors, but it's uncertain if all possible exploitation vectors would be covered. Upgrade of AngularJS to 1.8.0 is recommended.\n\n### References\nhttps://github.com/advisories/GHSA-mhp6-pxh8-r675\nhttps://github.com/jquery/jquery/security/advisories/GHSA-gxr4-xjj5-5px2\nhttps://github.com/jquery/jquery/security/advisories/GHSA-jpcq-cgw6-v4j6\nhttps://blog.jquery.com/2020/04/10/jquery-3-5-0-released/\nhttps://snyk.io/vuln/SNYK-JS-ANGULAR-570058",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "angular"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.8.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/google/security-research/security/advisories/GHSA-5cp4-xmrw-59wf"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jquery/jquery/security/advisories/GHSA-gxr4-xjj5-5px2"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jquery/jquery/security/advisories/GHSA-jpcq-cgw6-v4j6"
  }, {
    "type" : "WEB",
    "url" : "https://blog.jquery.com/2020/04/10/jquery-3-5-0-released"
  }, {
    "type" : "ADVISORY",
    "url" : "https://github.com/advisories/GHSA-mhp6-pxh8-r675"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/angular/angular.js"
  }, {
    "type" : "WEB",
    "url" : "https://snyk.io/vuln/SNYK-JS-ANGULAR-570058"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2020-08-05T21:46:46Z",
    "nvd_published_at" : null
  }
}