The Shellshock bug (CVE-2014-6271) is a serious vulnerability for websites and Internet-connected devices around the world. Also called “Bash” because it resides in the bash shell code in UNIX, Linux, and in hardware running Mac OSX, researchers compare its magnitude to Heartbleed (in fact, many are calling it way bigger), the Internet vulnerability we covered last spring in this remediation countdown.
The vulnerability enables attackers to gain access to a web server or device’s operating system and get to confidential information or make changes to the website or app. Software using Bash scripts is commonly used across the Internet (and across the Internet of Things). Any device that is connected to the Internet is potentially exploitable although servers connected directly to the Internet are the most easily exploitable.
One of the easiest ways for an attacker to exploit will be by using CGI. CGI — short for Common Gateway Interface — is one of the earliest methods of executing server side code on web servers and is still used by many sites and applications.
Any application that uses CGI is potentially vulnerable and exploitable. Netskope Cloud Confidence Index (CCI) tracks more than 5,000 applications and we know that some of these applications use CGI. We have reached out to application vendors to ensure that they are aware and can patch their systems.
What Should You Do?
Here’s what you can do to remediate your systems:
- Patch your systems. Patches are available from most Linux and UNIX vendors. Thus far, those patches have been incomplete, and can introduce other vulnerabilities (such as CVE-2014-7169).
- Analyze server side logs for suspicious activities.
We are providing our customers with details about vulnerable cloud apps as information becomes available.