DefenseCode ThunderScan SAST Advisory
          GOOGLE google-api-php-client
       Multiple Security Vulnerabilities

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/ E-mail: defensecode[at]defensecode.com Website: http://www.defensecode.com/ Twitter: https://twitter.com/DefenseCode/