DefenseCode ThunderScan SAST Advisory
GOOGLE google-api-php-client
Multiple Security Vulnerabilities
Advisory ID: DC-2017-04-012
Advisory Title: google-api-php-client Multiple XSS Vulnerabilities
Advisory URL:
http://defensecode.com/advisories/DC-2017-04-012_google-api-php-client_Advisory.pdf
Software: google-api-php-client
Software Language: PHP
Version: 2.1.3 and below
Vendor Status: Vendor contacted, vulnerability confirmed
Release Date: 2017-05-10
Risk: Medium
1. General Overview
===================
During the security audit of google-api-php-client (Google's PHP
client library for accessing Google APIs) multiple XSS vulnerabilities
were discovered using DefenseCode ThunderScan SAST application source
code security analysis platform.
More information about ThunderScan SAST is available at URL:
http://www.defensecode.com
2. Software Overview
====================
According to the API developers, the Google API Client Library enables
you to work with Google APIs such as Google+, Drive, or YouTube on
your server.
The developers further noted: "This client library is in beta. We will
make an effort to support the library and maintain backwards
compatibility in the future, but we reserve the right to make
incompatible changes when necessary."
Homepage:
https://developers.google.com/api-client-library/php/
https://github.com/google/google-api-php-client
3. Brief Vulnerability Description
==================================
During the security analysis, ThunderScan SAST discovered Cross Site
Scripting vulnerability in Google's PHP client library for accessing
Google APIs (google-api-php-client). The vulnerabilities were found in
the sample code for using the Google's URL Shortener.
The Cross-Site Scripting vulnerability can enable the attacker to
construct the URL that contains malicious JavaScript code. If the
administrator of the site makes a request to such an URL, the
attacker's code will be executed, with unrestricted access to the
site in question. The attacker can entice the administrator to visit
the URL in various ways, including sending the URL by email, posting
it as a part of the comment on the vulnerable site or another forum.
Once the unsuspecting user has visited such an URL, the attacker can
proceed to send requests to the API on the behalf of the victim from
his JavaScript.
3.1. Cross-Site Scripting
Vulnerable Function: <?= $_SERVER['PHP_SELF'] ?>
Variable: $_SERVER['PHP_SELF']
Vulnerable URL:
http://vulnerablesite.com/google-api-php-client/examples/url-shortener.php/%22%3E%3Cscript%3Ealert('xss')%3C/script%3E%3Cdc
File: google-api-php-client\examples\url-shortener.php
---------
118 <form id="url" method="GET" action="<?= $_SERVER['PHP_SELF'] ?>">
---------
3.2. Cross-Site Scripting
Vulnerable Function: <?= $_SERVER['PHP_SELF'] ?>
Variable: $_SERVER['PHP_SELF']
Vulnerable URL:
http://vulnerablesite.com/google-api-php-client/examples/url-shortener.php/%22%3E%3C/script%3E%3Cscript%3Ealert(42)%3C/script%3E?url=http%3A%2F%2Fwww.defensecode.com
File: google-api-php-client\examples\url-shortener.php
---------
129 <a href="<?= $_SERVER['PHP_SELF'] ?>">Create another</a>
---------
4. Solution
===========
Vendor is expected to resolve security issues in the next release. All
users are strongly advised to update google-api-php-client to the
latest available version.
5. Credits
==========
Discovered with DefenseCode ThunderScan SAST Source Code Security
Analyzer by Leon Juranic.
6. Disclosure Timeline
======================
2017/04/10 Vendor contacted
2017/04/15 Member of the Google Security Team responded:"Nice catch!"
2017/04/21 Google's Vulnerability Reward Program acknowledged
2017/05/10 Advisory released to the public
7. About DefenseCode ThunderScan SAST
=====================================
DefenseCode L.L.C. delivers products and services designed to analyze
and test web, desktop and mobile applications for security
vulnerabilities.
DefenseCode ThunderScan is a SAST (Static Application Security
Testing, WhiteBox Testing) solution for performing extensive security
audits of application source code. ThunderScan SAST performs fast and
accurate analyses of large and complex source code projects delivering
precise results and low false positive rate.
DefenseCode WebScanner is a DAST (Dynamic Application Security
Testing, BlackBox Testing) solution for comprehensive security audits
of active web applications. WebScanner will test a website's security
by carrying out a large number of attacks using the most advanced
techniques, just as a real attacker would.
Subscribe for free software trial on our website
http://www.defensecode.com/
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