Information Security Update: WannaCry ransomware attack, refocuses on why we need all security controls in place?? By Luv Johar
What exactly happened?
WannaCry, a crypto-ransomware that is also called WannaCrypt, affected at least 45,000 computers spread over 74 countries, including India, on Friday. The WanaCrypt0r 2.0 bug encrypts data on a computer within seconds and displays a message asking the user to pay a ransom of $ 300 in Bitcoins to restore access to the device and the data inside.
But what is ransomware? How is it different from other malicious software?
There are many types of malware that affect a computer, ranging from those that steal your information to those that just delete everything on the device. Ransomware, as the name suggests, prevents users from accessing their devices and data until a certain ransom is paid to its creator. Ransomware usually locks computers, encrypts the data on it and prevents software and apps from running.
Ransomware is a kind of cyber attack that involves hackers taking control of a computer system and blocking access to it until a ransom is paid.
For cyber criminals to gain access to the system they need to download a type of malicious software onto a device within the network. This is often done by getting a victim to click on a link or download it by mistake.
Once the software is on a victim’s computer the hackers can launch an attack that locks all files it can find within a network. This tends to be a gradual process with files being encrypted one after another.
Best practices to prevent ransomware attacks:
- Perform regular backups of all critical information to limit the impact of data or system loss and to help expedite the recovery process. Ideally, this data should be kept on a separate device, and backups should be stored offline.
- Establish a Sender Policy Framework (SPF), Domain Message Authentication Reporting and Conformance (DMARC), and DomainKeys Identified Mail (DKIM) for your domain, which is an email validation system designed to prevent spam by detecting email spoofing by which most of the ransomware samples successfully reaches the corporate email boxes.
- Don’t open attachments in unsolicited e-mails, even if they come from people in your contact list, and never click on a URL contained in an unsolicited e-mail, even if the link seems benign. In cases of genuine URLs close out the e-mail and go to the organization’s website directly through browser
- Restrict execution of PowerShell /WSCRIPT in enterprise environment Ensure installation and use of the latest version (currently v5.0) of PowerShell, with enhanced logging enabled. script block logging and transcription enabled. Send the associated logs to a centralized log repository for monitoring and analysis.
- Application whitelisting/Strict implementation of Software Restriction Policies (SRP) to block binaries running from %APPDATA%, %PROGRAMDATA%, and %TEMP% paths. Ransomware sample drops and executes generally from these locations. Enforce application whitelisting on all endpoint workstations.
- Deploy web and email filters on the network. Configure these devices to scan for known bad domains, sources, and addresses; block these before receiving and downloading messages. Scan all emails, attachments, and downloads both on the host and at the mail gateway with a reputable antivirus solution.
- Disable macros in Microsoft Office products. Some Office products allow for the disabling of macros that originate from outside of an organization and can provide a hybrid approach when the organization depends on the legitimate use of macros. For Windows, specific settings can block macros originating from the Internet from running.
- Configure access controls including file, directory, and network share permissions with least privilege in mind. If a user only needs to read specific files, they should not have write access to those files, directories, or shares.
- Maintain updated Antivirus software on all systems
- Consider installing Enhanced Mitigation Experience Toolkit, or similar host-level anti-exploitation tools.
- Block the attachments of file types, exe|pif|tmp|url|vb|vbe|scr|reg|cer|pst|cmd|com|bat|dll|dat|hlp|hta|js|wsf
- Regularly check the contents of backup files of databases for any unauthorized encrypted contents of data records or external elements, (backdoors /malicious scripts.)
- Keep the operating system third party applications (MS office, browsers, browser Plugins) up-to-date with the latest patches.
- Follow safe practices when browsing the web. Ensure the web browsers are secured enough with appropriate content controls.
- Network segmentation and segregation into security zones — help protect sensitive information and critical services. Separate administrative network from business processes with physical controls and Virtual Local Area Networks.
- Disable remote Desktop Connections, employ least-privileged accounts.
- Ensure integrity of the codes /scripts being used in database, authentication and sensitive systems, Check regularly for the integrity of the information stored in the databases.
- Restrict users’ abilities (permissions) to install and run unwanted software applications.
- Enable personal firewalls on workstations.
- Implement strict External Device (USB drive) usage policy.
- Employ data-at-rest and data-in-transit encryption.
- Carry out vulnerability Assessment and Penetration Testing (VAPT) and information security audit of critical networks/systems, especially database servers from CERT-IN empaneled auditors. Repeat audits at regular intervals.
- Individuals or organizations are not encouraged to pay the ransom, as this does not guarantee files will be released. Report such instances of fraud to CERT-In and Law Enforcement agencies
Some easy steps to protect yourself if you are an end user or home user :
- Keep your system Up-to-date: First of all, if you are using supported, but older versions of Windows operating system, keep your system up to date, or simply upgrade your system to Windows 10.
- Using Unsupported Windows OS? If you are using unsupported versions of Windows, including Windows XP, Vista, Server 2003 or 2008, apply the emergency patch released by Microsoft today.
- Enable Firewall: Enable firewall, and if it is already there, modify your firewall configurations to block access to SMB ports over the network or the Internet. The protocol operates on TCP ports 137, 139, and 445, and over UDP ports 137 and 138.
- Disable SMB: Follow steps described by Microsoft to disable Server Message Block (SMB).
- Keep your Antivirus software up-to-date: Virus definitions have already been updated to protect against this latest threat.
- Backup Regularly: To always have a tight grip on all your important files and documents, keep a good backup routine in place that makes their copies to an external storage device that is not always connected to your PC.
- Beware of Phishing: Always be suspicious of uninvited documents sent an email and never click on links inside those documents unless verifying the source.
Please leave any comments below in case of any queries & feel free to FOLLOW ME AT:
Linkedin: Linked In
Facebook: Facebook Page To Connect With Me
Facebook Group Page : ISMS Group
facebook Blog Page : Facebook Personal Blog
Google Group Page : Google+ ISMS Community