GHSA-66HF-2P6W-JQFW

Vulnerability from github – Published: 2021-12-08 19:57 – Updated: 2022-08-11 19:19
VLAI
Summary
Laravel Framework XSS in Blade templating engine
Details

A security researcher has disclosed a possible XSS vulnerability in the Blade templating engine.

Given the following two Blade templates:

resources/views/parent.blade.php:

@section('content')
<input value="{{ $value }}">
@show

resources/views/child.blade.php:

@extends('parent')

@section('content')
<input value="{{ $value }}">
@endsection

And a route like the following:

Route::get('/example', function() {
    $value = '//localhost/###parent-placeholder-040f06fd774092478d450774f5ba30c5da78acc8## onclick=location.assign(this.value);//';

    return view('child', ['value' => $value]);
});

The broken HTML element may be clicked and the user is taken to another location in their browser due to XSS. This is due to the user being able to guess the parent placeholder SHA-1 hash by trying common names of sections. If the parent template contains an exploitable HTML structure an XSS vulnerability can be exposed.

This vulnerability has been patched by determining the parent placeholder at runtime and using a random hash that is unique to each request.

Severity
6.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "laravel/framework"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.20.42"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "laravel/framework"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "7.0.0"
            },
            {
              "fixed": "7.30.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "laravel/framework"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.0.0"
            },
            {
              "fixed": "8.75.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "illuminate/view"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.20.42"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "illuminate/view"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "7.0.0"
            },
            {
              "fixed": "7.30.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "illuminate/view"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.0.0"
            },
            {
              "fixed": "8.75.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2021-43808"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-327",
      "CWE-79"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-12-07T21:33:14Z",
    "nvd_published_at": "2021-12-08T00:15:00Z",
    "severity": "MODERATE"
  },
  "details": "A security researcher has disclosed a possible XSS vulnerability in the Blade templating engine.\n\nGiven the following two Blade templates:\n\nresources/views/parent.blade.php:\n\n```html\n@section(\u0027content\u0027)\n\u003cinput value=\"{{ $value }}\"\u003e\n@show\n```\n\nresources/views/child.blade.php:\n\n```html\n@extends(\u0027parent\u0027)\n\n@section(\u0027content\u0027)\n\u003cinput value=\"{{ $value }}\"\u003e\n@endsection\n```\n\nAnd a route like the following:\n\n```php\nRoute::get(\u0027/example\u0027, function() {\n    $value = \u0027//localhost/###parent-placeholder-040f06fd774092478d450774f5ba30c5da78acc8## onclick=location.assign(this.value);//\u0027;\n\n    return view(\u0027child\u0027, [\u0027value\u0027 =\u003e $value]);\n});\n```\n\nThe broken HTML element may be clicked and the user is taken to another location in their browser due to XSS. This is due to the user being able to guess the parent placeholder SHA-1 hash by trying common names of sections. If the parent template contains an exploitable HTML structure an XSS vulnerability can be exposed.\n\nThis vulnerability has been patched by determining the parent placeholder at runtime and using a random hash that is unique to each request.",
  "id": "GHSA-66hf-2p6w-jqfw",
  "modified": "2022-08-11T19:19:57Z",
  "published": "2021-12-08T19:57:36Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/laravel/framework/security/advisories/GHSA-66hf-2p6w-jqfw"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-43808"
    },
    {
      "type": "WEB",
      "url": "https://github.com/laravel/framework/pull/39906"
    },
    {
      "type": "WEB",
      "url": "https://github.com/laravel/framework/pull/39908"
    },
    {
      "type": "WEB",
      "url": "https://github.com/laravel/framework/pull/39909"
    },
    {
      "type": "WEB",
      "url": "https://github.com/laravel/framework/commit/b8174169b1807f36de1837751599e2828ceddb9b"
    },
    {
      "type": "WEB",
      "url": "https://github.com/FriendsOfPHP/security-advisories/blob/master/illuminate/view/CVE-2021-43808.yaml"
    },
    {
      "type": "WEB",
      "url": "https://github.com/FriendsOfPHP/security-advisories/blob/master/laravel/framework/CVE-2021-43808.yaml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/laravel/framework"
    },
    {
      "type": "WEB",
      "url": "https://github.com/laravel/framework/releases/tag/v6.20.42"
    },
    {
      "type": "WEB",
      "url": "https://github.com/laravel/framework/releases/tag/v7.30.6"
    },
    {
      "type": "WEB",
      "url": "https://github.com/laravel/framework/releases/tag/v8.75.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Laravel Framework XSS in Blade templating engine"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON
How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.