New warnings about potentially malicious binaries

Posted by Moheeb Abu Rajab, Security Team

If you use Chrome, you shouldn’t have to work hard to know what Chrome extensions you have installed and enabled. That’s why last December we announced that Chrome (version 25 and beyond) would disable silent extension installation by default. In addition to protecting users from unauthorized installations, these measures resulted in noticeable performance improvements in Chrome and improved user experience.

To further safeguard you while browsing the web, we recently added new measures to protect you and your computer. These measures will identify software that violates Chrome’s standard mechanisms for deploying extensions, flagging such binaries as malware. Within a week, you will start seeing Safe Browsing malicious download warnings when attempting to download malware identified by this criteria.

This kind of malware commonly tries to get around silent installation blockers by misusing Chrome’s central management settings that are intended be used to configure instances of Chrome internally within an organization. In doing so, the installed extensions are enabled by default and cannot be uninstalled or disabled by the user from within Chrome. Other variants include binaries that directly manipulate Chrome preferences in order to silently install and enable extensions bundled with these binaries. Our recent measures expand our capabilities to detect and block these types of malware.

Application developers should adhere to Chrome’s standard mechanisms for extension installation, which include the Chrome Web Store, inline installation, and the other deployment options described in the extensions development documentation.