Google has released a new network traffic security testing tool that can be used to check if devices and applications are impacted by Transport Layer Security/ Secure Sockets Layer (TLS/SSL) vulnerabilities and if the cryptographic protocols are configured correctly.
The tool, dubbed Nogotofail, has been used internally by the Android Security Team for some time. However, on Tuesday, it was released as an open source project to allow anyone to test their applications and contribute to making the tool better.
“Nogotofail works for Android, iOS, Linux, Windows, Chrome OS, OSX, in fact any device you use to connect to the Internet. There’s an easy-to-use client to configure the settings and get notifications on Android and Linux, as well as the attack engine itself which can be deployed as a router, VPN server, or proxy,” Android Security Engineer Chad Brubaker, one of the tool’s developers, wrote in a post on the Google Online Security blog.
The documentation published for Nogotofail shows that the tool is composed of an on-path network man-in-the-middle (MitM) component that intercepts TCP traffic, and optional clients that can be installed on the tested devices. These clients run on the device and communicate with the MitM to help determine which component or app made a vulnerable connection.
“[Nogotofail] includes testing for common SSL certificate verification issues, HTTPS and TLS/SSL library bugs, SSL and STARTTLS stripping issues, cleartext issues, and more,” Brubaker wrote in the release notes.
Google released the tool following multiple reports of TLS/SSL flaws. In fact, the name of the tool is inspired by “goto fail,” the SSL bug affecting Apple’s iOS and OS X operating systems (CVE-2014-1266).
Just weeks before the existence of the iOS/OS X issue came to light, researchers reported uncovering a new vulnerability in the TLS and Datagram TLS (DTLS) protocols that could be exploited to recover plaintext from a TLS/DTLS connection when CBC-mode encryption is used.
An even more serious vulnerability was disclosed in April. The Heartbleed bug (CVE-2014-0160), which affects the OpenSSL cryptographic library, is more than just a theoretical flaw. Malicious actors leveraged Heartbleed on multiple occasions to gain access to sensitive data.
More recently, researchers uncovered POODLE, a flaw in SSL 3.0 (CVE-2014-3566) that can be leveraged to extract sensitive information from encrypted communications. Last week, Google announced its intention to completely disable SSL 3.0 in the upcoming versions of the Chrome Web browser.