-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 ============================================================================= pfSense-SA-20_07.webgui Security Advisory pfSense Topic: XSS vulnerability in the WebGUI Category: pfSense Base System Module: webgui Announced: 2020-03-18 Credits: Jonathan MERESSE Affects: pfSense software versions <= 2.4.4-p3 Corrected: 2020-03-18 13:55:31 UTC (pfSense/master, pfSense 2.5.0) 2020-03-18 13:56:06 UTC (pfSense/RELENG_2_4_5, pfSense 2.4.5) 0. Revision History v1.0 2020-03-18 Initial SA draft I. Background pfSense® software is a free network firewall distribution based on the FreeBSD operating system. The pfSense software distribution includes third- party free software packages for additional functionality, and provides most of the functionality of common commercial firewalls. The majority of users of pfSense software have never installed or used a stock FreeBSD system. Unlike similar GNU/Linux-based firewall distributions, there is no need for any UNIX knowledge. The command line is never used, and there is no need to ever manually edit any rule sets. Instead, pfSense software includes a web interface for the configuration of all included components. Users familiar with commercial firewalls will quickly understand the web interface, while those unfamiliar with commercial-grade firewalls may encounter a short learning curve. II. Problem Description A Cross-Site Scripting (XSS) vulnerability was found in diag_ping.php, a component of the pfSense software WebGUI, on version 2.4.4-p3 and earlier. The page did not validate the contents of the host parameter nor did it encode the output which could have included this value, leading to a possible XSS. III. Impact Due to the lack of proper encoding on the affected parameters susceptible to XSS, arbitrary JavaScript could be executed in the user's browser. The user's session cookie or other information from the session may be compromised. IV. Workaround To help mitigate the problem on older releases, use one or more of the following: * Limit access to the affected pages to trusted administrators only. * Do not log into the firewall with the same browser used for non- administrative web browsing. V. Solution Users can upgrade to version 2.4.5 or later. This upgrade may be performed in the web interface or from the console. See https://docs.netgate.com/pfsense/en/latest/install/upgrade-guide.html Users may also apply the relevant revisions below using the System Patches package on pfSense 2.4.4-p3. See https://docs.netgate.com/pfsense/en/latest/development/system-patches.html VI. Correction details The following list contains the correction revision commit ID for each affected item. Branch/path Revision - - ------------------------------------------------------------------------- pfSense/master cc3990a334059018b004c91eeb66c147d8afe83d pfSense/RELENG_2_4_5 f3761c151782aafd90c7534b2ecb98191096a22b - - ------------------------------------------------------------------------- VII. References The latest revision of this advisory is available at -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEE40XvjEU56XSUPIMdE7mH/ZIU+NoFAl5yLi8ACgkQE7mH/ZIU +NoTxA//St4uiW3wvR9T2hOnsXypXIfEHmBjcwIyeYnKQybNt4wefDUOB6KPSM1D Gil8qSaWZ7RIa70dtxz2mtgY2/7Xnn/Bw6V2jhRvOGodZkrcTqZuf7eK//F+rW2L BbaH/k2Luw60fN74FP7q6eusS9wdvy5qB1jam+gkt21avqpQZOwha+YLTKbRD+7z NDMZHwDa8JW1lQWJorVElYdsnwzhz2Bjw+biZqzj5aX1PhZ8Rs9wQK2GZt7jri0o D0btd/05u8A5TUBK+Ytmjv+ccf8lX/xDO8DIdvKhSgNfllBOUaUw26UU86U1HfgE jCIiFTan791WJrWUEVAxvfQ/d5YK/IdVZZPn8jK8qeS8ub/jlCldN7oDraEqjCHU kgb87SkiCX/LzVWULqW1YIyydaKf8/JkGx3D410Mi0sKV8voA/1jREReawpmhwKT 0rW2B9WBDUzo8ACidcOcm9zYaAhC7kvEgUhd0+W4pZhrBfWjUsHWJIy1Y9AWJMIJ bnQ9tbpg9f/b0e7vdpfOd1JdUzLlNVgt6yx13lXCbVI7+Jd4AV76Hq7zsc10SdRs /f4C51lAXATWjX1gCNvrffiMYx7LIvWX3vv5XCjYTRSoK3WXqDOOZPSCvcmfaLhC JFqOaIvcoX8MKs47Q85vtglLA+5/0XrDhmf2JpzGYhjX2jOQmyc= =jtMO -----END PGP SIGNATURE-----