CVE-2021-39286 (published 2021-08-18T18:15Z)

Webrecorder pywb before 2.6.0 allows XSS because it does not ensure that Jinja2 templates are autoescaped.

Severity: MEDIUM
CVSS v2 base score: 4.3 (AV:N/AC:M/Au:N/C:N/I:P/A:N)
CVSS v3 base score: 6.1, MEDIUM (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N)

Weakness information:
cwe_id: CWE-79
cwe_name: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
description: The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
extended_description: 
            Cross-site scripting (XSS) vulnerabilities occur when:
            
               Untrusted data enters a web application, typically from a web request.
               The web application dynamically generates a web page that contains this untrusted data.
               During page generation, the application does not prevent the data from containing content that is executable by a web browser, such as JavaScript, HTML tags, HTML attributes, mouse events, Flash, ActiveX, etc.
               A victim visits the generated web page through a web browser, which contains malicious script that was injected using the untrusted data.
               Since the script comes from a web page that was sent by the web server, the victim's web browser executes the malicious script in the context of the web server's domain.
               This effectively violates the intention of the web browser's same-origin policy, which states that scripts in one domain should not be able to access resources or run code in a different domain.
            
            There are three main kinds of XSS:
            
               
                  Type 1: Reflected XSS (or Non-Persistent) - 
         			The server reads data directly from the HTTP request and reflects it back in the HTTP response. Reflected XSS exploits occur when an attacker causes a victim to supply dangerous content to a vulnerable web application, which is then reflected back to the victim and executed by the web browser. The most common mechanism for delivering malicious content is to include it as a parameter in a URL that is posted publicly or e-mailed directly to the victim. URLs constructed in this manner constitute the core of many phishing schemes, whereby an attacker convinces a victim to visit a URL that refers to a vulnerable site. After the site reflects the attacker's content back to the victim, the content is executed by the victim's browser.
               
                  Type 2: Stored XSS (or Persistent) - 
               The application stores dangerous data in a database, message forum, visitor log, or other trusted data store. At a later time, the dangerous data is subsequently read back into the application and included in dynamic content. From an attacker's perspective, the optimal place to inject malicious content is in an area that is displayed to either many users or particularly interesting users. Interesting users typically have elevated privileges in the application or interact with sensitive data that is valuable to the attacker. If one of these users executes malicious content, the attacker may be able to perform privileged operations on behalf of the user or gain access to sensitive data belonging to the user. For example, the attacker might inject XSS into a log message, which might not be handled properly when an administrator views the logs.
            
               
                  Type 0: DOM-Based XSS - 
               In DOM-based XSS, the client performs the injection of XSS into the page; in the other types, the server performs the injection. DOM-based XSS generally involves server-controlled, trusted script that is sent to the client, such as Javascript that performs sanity checks on a form before the user submits it. If the server-supplied script processes user-supplied data and then injects it back into the web page (such as with dynamic HTML), then DOM-based XSS is possible.
            
            
            Once the malicious script is injected, the attacker can perform a variety of malicious activities. The attacker could transfer private information, such as cookies that may include session information, from the victim's machine to the attacker. The attacker could send malicious requests to a web site on behalf of the victim, which could be especially dangerous to the site if the victim has administrator privileges to manage that site. Phishing attacks could be used to emulate trusted web sites and trick the victim into entering a password, allowing the attacker to compromise the victim's account on that web site. Finally, the script could exploit a vulnerability in the web browser itself possibly taking over the victim's machine, sometimes referred to as "drive-by hacking."
            In many cases, the attack can be launched without the victim even being aware of it. Even with careful users, attackers frequently use a variety of methods to encode the malicious portion of the attack, such as URL encoding or Unicode, so the request looks less suspicious.
         
         

Fix information:
repo_url: https://github.com/webrecorder/pywb
commit_details: repo_url: https://github.com/webrecorder/pywb
author: Ilya Kreymer
author_date: 2021-06-14 17:09:00-07:00
msg: Localization / doc fixes (#650)

* localization / doc fixes:
- add missing header.html
- docs: support 'i18n' extra, mention in docs
- use 'default_locale' for html lang tag
- access control docs: fix documentation for adding user with acl command

* localization: add compile_catalog after extract as well to simplify updates for identity (en) locale

* ui: 
- include locale in home page collection listing
- keep locale on error page home link

* autoescape:
- ensure jinja2 templates are autoescaped to prevent xss issues (thanks @sebastian-nagel for suggested fix)
- ensure banner inserts are not double-escaped
- update tests for template autoescaping

* update CHANGES.rst

* bump version to 2.6.0b1
repository: repo_url: https://github.com/webrecorder/pywb
repo_name: webrecorder/pywb
description: Core Python Web Archiving Toolkit for replay and recording of web archives
repo_language: JavaScript
owner: webrecorder
file_changes: filename: CHANGES.rst
change_type: ModificationType.MODIFY
diff: @@ -1,3 +1,17 @@
+pywb 2.6.0b1 changelist
+~~~~~~~~~~~~~~~~~~~~~~~
+
+Additional documentation / localization fixes `#650 <https://github.com/webrecorder/pywb/pull/650>`_
+
+* Ensure home page and error page keeps locale, language switching is working.
+
+* Add autoescaping to Jinja2 to avoid XSS issues (suggested by @sebastian-nagel)
+
+* Add support for 'pywb[i18n]' extra to install localization dependencies
+
+Documentation typo fixes (by @ldko, `#649 <https://github.com/webrecorder/pywb/pull/649>`_)
+
+
 pywb 2.6.0b0 changelist
 ~~~~~~~~~~~~~~~~~~~~~~~
 

programming_language: Markdown
filename: config.yaml
change_type: ModificationType.MODIFY
diff: @@ -17,6 +17,3 @@ enable_memento: true
 # Replay content in an iframe
 framed_replay: true
 
-locales:
-  - en
-  - es

programming_language: Shell
filename: access-control.rst
change_type: ModificationType.MODIFY
diff: @@ -187,7 +187,7 @@ The URL supplied can be a URL or a SURT prefix. If a SURT is supplied, it is use
 
 A specific user for user-based rules can also be specified, for example to add ``allow_ignore_embargo`` for user ``staff`` only, run::
 
-  wb-manager acl add <collection> http://httpbin.org/anything/something allow_ignore_embargo staff
+  wb-manager acl add <collection> http://httpbin.org/anything/something allow_ignore_embargo -u staff
 
 
 By default, access control rules apply to a prefix of a given URL or SURT.

programming_language: Markdown
filename: localization.rst
change_type: ModificationType.MODIFY
diff: @@ -9,10 +9,15 @@ pywb can extract all text from templates and generate CSV files for translation
 
 (pywb uses the `Babel library <http://babel.pocoo.org/en/latest/>`_  which extends the `standard Python i18n system <https://docs.python.org/3/library/gettext.html>`_)
 
+To ensure all localization related dependencies are installed, first run::
+
+  pip install pywb[i18n]
+
 Locales to use are configured in the ``config.yaml``.
 
 The command-line ``wb-manager`` utility provides a way to manage locales for translation, including generating extracted text, and to update translated text.
 
+
 Adding a Locale and Extracting Text
 ===================================
 

programming_language: Markdown
filename: locmanager.py
change_type: ModificationType.MODIFY
diff: @@ -41,6 +41,8 @@ class LocManager:
                 csv = os.path.join(base, 'messages.csv')
                 po2csv([po, csv])
 
+        self.compile_catalog()
+
     def update_loc(self, locale, no_csv):
         for loc in locale:
             if not no_csv:

programming_language: Python
filename: templateview.py
change_type: ModificationType.MODIFY
diff: @@ -5,7 +5,7 @@ from pywb.utils.loaders import load
 
 from six.moves.urllib.parse import urlsplit, quote
 
-from jinja2 import Environment, TemplateNotFound, contextfunction
+from jinja2 import Environment, TemplateNotFound, contextfunction, select_autoescape
 from jinja2 import FileSystemLoader, PackageLoader, ChoiceLoader
 
 from babel.support import Translations
@@ -77,10 +77,12 @@ class JinjaEnv(object):
 
         if overlay:
             jinja_env = overlay.jinja_env.overlay(loader=loader,
+                                                  autoescape=select_autoescape(),
                                                   trim_blocks=True,
                                                   extensions=extensions)
         else:
             jinja_env = RelEnvironment(loader=loader,
+                                       autoescape=select_autoescape(),
                                        trim_blocks=True,
                                        extensions=extensions)
 

programming_language: Python
filename: base.html
change_type: ModificationType.MODIFY
diff: @@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html lang="{{ env.pywb_lang | default('en') }}">
+<html lang="{{ env.pywb_lang | default(default_locale) }}">
     <head>
         <meta http-equiv="content-type" content="text/html; charset=UTF-8;charset=utf-8"/>
         <meta name="viewport" content="width=device-width, initial-scale=1">

programming_language: HTML
filename: error.html
change_type: ModificationType.MODIFY
diff: @@ -13,7 +13,7 @@
         {% elif err_status == 404 and err_details == 'coll_not_found' %}
             <p>{% trans %}Collection not found: <b>{{ err_msg }}{% endtrans %}</b></p>
 
-            <p><a href="/">{{ _('See list of valid collections') }}</a></p>
+            <p><a href="/{{ env.pywb_lang | default('') }}">{{ _('See list of valid collections') }}</a></p>
 
         {% elif err_status == 404 and err_details == 'static_file_not_found' %}
             <p>{% trans %}Static file not found: <b>{{ err_msg }}{% endtrans %}</b></p>

programming_language: HTML
filename: frame_insert.html
change_type: ModificationType.MODIFY
diff: @@ -14,8 +14,12 @@ html, body
 </style>
 <script src='{{ static_prefix }}/wb_frame.js'> </script>
 
+{% autoescape false %}
+
 {{ banner_html }}
 
+{% endautoescape %}
+
 </head>
 <body style="margin: 0px; padding: 0px;">
 

programming_language: HTML
filename: head_insert.html
change_type: ModificationType.MODIFY
diff: @@ -1,3 +1,5 @@
+{% autoescape false %}
+
 <!-- WB Insert -->
 <script>
 {% set urlsplit = cdx.url | urlsplit %}
@@ -61,5 +63,7 @@
 
 {{ banner_html }}
 
+{% endautoescape %}
+
 <!-- End WB Insert -->
 

programming_language: HTML
filename: header.html
change_type: ModificationType.ADD
diff: @@ -0,0 +1,13 @@
+<header>
+   {% if locales|length > 1 %}
+    <div class="language-select">
+        {{ _('Language:') }}
+        <ul role="listbox" aria-activedescendant="{{ env.pywb_lang | default(default_locale) }}" aria-labelledby="{{ _('Language select') }}">
+        {% for locale in locales %}
+          <li role="option" id="{{ locale }}"><a href="{{ switch_locale(locale) }}">{{ locale }}</a></li>
+        {% endfor %}
+        </ul>
+    </div>
+    {% endif %}
+</header>
+

programming_language: HTML
filename: index.html
change_type: ModificationType.MODIFY
diff: @@ -9,7 +9,7 @@
         <ul>
             {% for route in routes %}
                 <li>
-                    <a href="{{ env['pywb.app_prefix'] + '/' + route }}">{{ '/' + route }}</a>
+                    <a href="{{ env['pywb.app_prefix'] + ('/' + env.pywb_lang if env.pywb_lang else '') + '/' + route }}">{{ '/' + route }}</a>
                     {% if all_metadata and all_metadata[route] %}
                         ({{ all_metadata[route].title }})
                     {% endif %}

programming_language: HTML
filename: version.py
change_type: ModificationType.MODIFY
diff: @@ -1,4 +1,4 @@
-__version__ = '2.6.0b0'
+__version__ = '2.6.0b1'
 
 if __name__ == '__main__':
     print(__version__)

programming_language: Python
filename: setup.py
change_type: ModificationType.MODIFY
diff: @@ -107,6 +107,9 @@ setup(
          glob.glob('sample_archive/text_content/*')),
     ],
     install_requires=load_requirements('requirements.txt'),
+    extras_require={
+        "i18n":  ["translate_toolkit"],
+    },
     tests_require=[
         'pytest',
         'WebTest',

programming_language: Python
filename: test_auto_colls.py
change_type: ModificationType.MODIFY
diff: @@ -313,15 +313,16 @@ class TestManagedColls(CollsDirMixin, BaseConfigTest):
         assert resp.status_int == 200
         assert resp.content_type == 'text/html'
         assert 'overriden search page: ' in resp.text
-        print(resp.text)
-        assert '"some":"value"' in resp.text, resp.text
+        #assert '"some":"value"' in resp.text, resp.text
+        assert '{&#34;some&#34;:&#34;value&#34;}' in resp.text, resp.text
 
     def test_replay_banner_metadata(self, fmod):
         """ Test adding metadata in replay banner (both framed and non-frame)
         """
         resp = self.get('/test/20140103030321{0}/http://example.com/?example=1', fmod)
         assert '<div>Custom Banner Here!</div>' in resp.text
-        assert '"some":"value"' in resp.text
+        #assert '"some":"value"' in resp.text
+        assert '{&#34;some&#34;:&#34;value&#34;}' in resp.text, resp.text
 
     def test_more_custom_templates_replay(self, fmod):
         resp = self.get('/test/20140103030321{0}/http://example.com/?example=1', fmod)

programming_language: Python