It seems like yesterday that Heartbleed stormed the Internet, it affected nearly two-thirds of websites online and allowed hackers to access data servers. But now, another widespread vulnerability of Bash known as Shellshock has been discovered, that is likely to affect millions of systems, servers and users. By executing this vulnerability, an attacker can easily execute an attack as it requires minimum technical knowledge to do so.
What is Shellshock?
Shellshock is a pair of vulnerabilities in the Bash command shell, which is commonly used by most Linux distributions, BSD, and Mac OS X. Bash command shell basically uses a command-line interface to access any services of the operating system and execute commands on a computer. Hence, the Shellshock vulnerability when exploited allows an attacker to execute any commands on an affected system.
Exploitation of this vulnerability can pose serious threat, as a majority of the web servers and other Internet-connected devices such as mobile phones, routers, and other IoT (Internet of Things) devices are running a Linux or UNIX-based version of operating system.
Shellshock vulnerability creates a backdoor for attackers that allow them to execute malicious commands remotely. It permits attackers to run malicious scripts in systems and servers, launch DDoS attacks, dig into web- servers, modify the contents of the web server, spread malware, create bots, send spam and phishing emails, access and steal sensitive information and damage websites.
Which devices are affected?
All the Unix-based operating systems such as Linux and Mac OS X are likely to be affected. Computers, Servers and Internet-connected home devices such as routers, refrigerators, password-protected door alarms, Webcams, Wi-Fi radios running on Linux OS are most likely affected.
Which versions of Bash are affected?
All versions of Bash up to and including version 4.3 are vulnerable. Check with your *nix vendor’s website for specific patched versions. Update to the latest version of bash immediately. US-CERT advises that people stay tuned for updates to get the latest patch.
How can you protect yourself?
To effectively mitigate the Shellshock vulnerability, here is what you need to do:
As an end user,
- Be alert and proactive.
- Apply all software updates and use effective antivirus software for your mobile and PC.
- Watch for patches and implement them on your Linux, Mac, Android and other IoT devices as soon as you receive them.
- Use Shellshock detection tool to find out if your system is affected and take necessary steps.
As an IT Admin,
- Keep a watch on the network activity.
- Disable bash scripting on Linux systems immediately.
- Use Shellshock detection tool to find out if your system is affected and take necessary steps.
- Patch infected systems, as soon as you receive any update from you provider.
