Securing Computers: Preventing Unauthorized Changes

In today's digital world, it is crucial to protect our computer systems from unauthorized changes and potential security threats. Whether it's personal information, sensitive work documents, or critical business data, ensuring the integrity and security of our computers is essential. By implementing robust measures, we can safeguard our devices from unwanted modifications, malicious software, and unauthorized access. This involves a comprehensive approach, including regular software updates, utilizing security tools, enabling authentication protocols, and educating users about secure practices. Through these proactive steps, we can maintain the stability, security, and privacy of our computer systems, preventing unauthorized changes and mitigating potential risks. This guide will explore these strategies in detail, offering valuable insights to help individuals and organizations secure their valuable digital assets.

Set Up Admin Controls: Restrict access with admin controls and passwords to prevent unauthorized changes

Setting up admin controls and restricting access with passwords are essential steps to prevent unauthorized changes to a computer. Here are some detailed instructions to help achieve this:

Understand User Roles and Access Privileges:

Firstly, it is crucial to understand the different user roles and their respective access privileges. In a typical organization, there are standard users and administrators. Standard users should only have the permissions necessary to perform their routine tasks, adhering to the principle of least privilege. On the other hand, administrators have elevated privileges to manage and configure the system.

Implement Role-Based Access Control (RBAC):

RBAC involves assigning specific roles to users, granting them only the permissions required to fulfill their job functions. This minimizes the risk of unauthorized changes by limiting access to sensitive areas. For example, a user responsible for managing DNS zones might only need access to the DNS Admins group.

Use Strong Password Policies:

Enforce strong password policies for all users, including administrators. Strong passwords should be lengthy (at least 8 characters), contain a mix of uppercase and lowercase letters, include numerical and special characters, and not be based on easily guessable information. Additionally, consider implementing regular password changes and avoiding password reuse.

Utilize Multi-Factor Authentication (MFA):

Supplement knowledge-based authentication factors (usernames and passwords) with additional factors such as possession factors (e.g., mobile phone or security token) and inherence factors (e.g., biometric authentication like fingerprints or iris scans). MFA adds an extra layer of security, making it harder for unauthorized individuals to gain access.

Control Access to Admin Accounts:

Restrict access to administrative accounts to prevent unauthorized changes. Implement strict controls and regularly audit these accounts. Ensure that only authorized individuals can modify admin account details, and consider using smart cards or other certificate-based authentication mechanisms for added security.

Monitor User Activity:

Implement monitoring solutions to detect anomalous user activity. This includes monitoring login attempts, especially during unusual hours, and tracking access to sensitive data or systems. By analyzing user behavior, you can identify potential unauthorized access attempts and respond accordingly.

Secure Local Administrator Accounts:

For computers joined to a domain, ensure that local administrator accounts are disabled by default. If local Administrator accounts are enabled, implement controls to restrict their use. For example, you can add the Administrator account to specific user rights in Group Policy Objects (GPOs) to deny access from the network, deny logon as a batch job, or deny logon through Remote Desktop Services.

User Education and Training:

Educate users about the importance of security and the potential risks of unauthorized access. Train them to follow secure practices, such as not sharing passwords, locking devices when away from their desks, and being cautious when reading emails and downloading attachments. User awareness plays a vital role in preventing unauthorized access.

By implementing these measures, you can effectively restrict access and prevent unauthorized changes to your computer systems.

Use Device Encryption: Encrypt devices to secure data and ensure only authorized users can access

Device encryption is a critical component of data protection, ensuring that sensitive information stored on computers and other devices remains secure and accessible only to authorized individuals. This process involves transforming data into a concealed code, which can only be deciphered by those possessing the correct decryption key. By encrypting devices, users can safeguard their data from unauthorized access, ensuring that even if a device falls into the wrong hands, the information stored on it remains protected.

One of the most prominent methods for device encryption is the use of BitLocker, a standard encryption tool available on Windows devices. To enable BitLocker, users need to sign in to their Windows device with an administrator account. From there, they can access the device's settings and turn on BitLocker drive encryption. This process will vary slightly depending on the specific version of Windows being used. It is important to note that BitLocker may not be available on all Windows editions, such as the Windows 10 and 11 Home editions.

For macOS users, a similar process can be achieved using the Finder app. By opening the Disk Utility app and selecting their desired storage device, users can choose to erase and encrypt their drive, formatting it with the macOS Extended (Journaled) file system. This ensures that all data stored on the device is protected and secure.

In addition to these built-in tools, there are also third-party software options available, such as Veracrypt for Windows users. These tools provide users with additional options for encrypting their devices and protecting their data.

It is worth noting that while device encryption is a powerful security measure, it should be used in conjunction with other security practices. Implementing strong password policies, regularly updating software, and utilizing multi-factor authentication can further enhance the security of encrypted devices. By combining device encryption with these additional measures, users can create a robust defence against unauthorized access and data breaches.

Regular Backups: Regularly back up data to restore devices to previous states if changes occur

Regular backups are essential to ensuring data protection and quick recovery in the event of equipment failure, cyberattack, natural disaster, or other data loss incidents. Here are some key considerations for implementing a regular backup strategy:

Full Backup:

• A full backup involves creating a complete copy of all files, folders, SaaS data, and hard drives.
• It is the most time-consuming type of backup and may strain the network during the backup process.
• However, it is the quickest to restore from, as all necessary files are contained in a single backup set.
• Full backups require the most storage space and can be costly.
• Small businesses with smaller data volumes may find full backups ideal as they are easy to maintain and restore.

Incremental Backup:

• An incremental backup only backs up data that has changed since the last backup, regardless of the type (full or incremental).
• This method takes less space and time compared to full and differential backups.
• Incremental backups are ideal for large businesses dealing with vast amounts of data as they encourage fast backups and efficient use of storage space.
• However, restoration can be time-consuming, as data needs to be pieced together from multiple backup sets.

Differential Backup:

• A differential backup copies data that has changed since the last full backup, not the last differential or incremental backup.
• It is a compromise between full and incremental backups, taking less space than full backups but more than incremental backups.
• Restoration is faster than incremental backups but slower than full backups.
• Differential backups are suitable for small to medium-sized organizations that want to process large volumes of data but cannot perform constant backups.

Backup Frequency and Storage:

• The frequency of full backups depends on factors such as data criticality and how often it changes.
• Full backups are typically scheduled daily, weekly, or at other intervals during off-peak hours to reduce performance impact.
• Differential or incremental backups can be scheduled in between full backups to capture new or changed data.
• When choosing a storage medium (tape, disk, cloud, etc.), consider factors such as security, capacity, performance, and cost.

Data Protection and Security:

• Implement encryption to protect your backup data from unauthorized access.
• Ensure that your backup data is stored securely, preferably in an off-site location or using cloud-based solutions.
• Regularly test your backup processes to confirm they are working correctly and to identify any necessary adjustments.

By following these guidelines and choosing the appropriate backup methods for your specific needs, you can ensure that your data is protected and that you have the ability to restore devices to their previous states if changes occur.

Anti-Virus Software: Install anti-virus software to detect and remove malicious programs that may alter systems

Anti-virus software is a critical tool for protecting your computer from malicious software, or malware, which is designed to damage data or your computer system. By installing anti-virus software, you can detect and remove malware, preventing it from interfering with your computer's operation and protecting your data. Here are some essential steps and considerations for using anti-virus software effectively:

Choose and Install Reputable Anti-Virus Software

Select a well-known and trusted anti-malware program such as Avast One, which offers free real-time anti-malware protection. It is essential to install the software properly and ensure it is configured correctly for your system.

Keep Your Anti-Virus Software Up to Date

Anti-virus software relies on having the latest updates to detect new and evolving malware. Set your software to update automatically, so you always have the latest version and malware definitions. This ensures that your computer has the best protection against the latest threats.

Configure Automatic Scans

Most anti-virus software can be set to automatically scan specific files or directories in real time. This helps detect malware early and prevents infection. You can also set the software to prompt you at regular intervals to perform complete scans of your system.

Understand Manual Scanning

For files received from external sources, such as email attachments or downloads, it is good practice to manually scan them before opening. Save these files and scan them separately, rather than opening them directly. This includes scanning media like CDs and DVDs for malware before accessing any files.

Understand How Your Software Responds to Threats

Familiarize yourself with how your chosen anti-virus software responds when it detects a threat. Some software will produce a dialog box alerting you to the presence of malware and ask if you want to "clean" the file. Other software may attempt to remove the malware without your input. Knowing how your software behaves will help you respond appropriately to any alerts.

Take Other Security Precautions

While anti-virus software is essential, it has limitations and cannot detect all forms of malware. Therefore, it is crucial to take other security precautions. Be cautious when opening email attachments, downloading files, or visiting unfamiliar websites. Keep your computer's operating system and other software up to date, as updates often include security patches. Additionally, use a firewall for added protection, and be vigilant for any suspicious activity.

By following these steps and staying vigilant, you can significantly enhance the security of your computer system and protect your data from malicious programs.

User Training: Educate users on security practices to prevent accidental or intentional changes

Security awareness training is a critical component of any organization's cybersecurity strategy. It empowers employees to recognize and mitigate cyber risks, fostering a culture of vigilance and resilience. The training covers various topics such as password security, phishing attacks, social engineering, malware, and more. Here are some detailed instructions to educate users on security practices:

Emphasize the Importance of Data Security:

Employees should understand the critical nature of protecting company data. They have legal and regulatory obligations to respect and protect the privacy, integrity, and confidentiality of information. Emphasize that data breaches can result in significant financial losses and reputation damage.

Implement Regular Training and Refresher Courses:

New hire training is essential, but it's not enough. Employees need periodic refresher courses to retain security practices over time. Make security awareness training an ongoing process, conducting sessions at least annually or more frequently for better retention.

Password Security:

Teach employees how to create strong, cryptic passwords that are difficult to guess. Encourage the use of randomized passwords and two-factor authentication for added security. Ensure they understand the importance of not writing down passwords and regularly changing them.

Phishing Attacks and Social Engineering:

Phishing attacks are a significant threat to organizations, and employees need to be able to recognize and report them. Train them to identify suspicious emails, links, or attachments. Educate them about social engineering tactics, such as impersonation or offering incentives, used by attackers to gain sensitive information.

Unauthorized Software and Safe Browsing:

Make employees aware that they are not allowed to install unlicensed software, as it may contain malicious programs. Establish safe browsing rules and limits on employee internet usage. Train them to avoid suspicious links and only download software from trusted sources.

Email Security:

Educate employees on responsible email usage, including recognizing scams and only accepting emails from trusted sources. Train them to be cautious of emails with unusual spellings or characters and to report any suspicious emails to the IT team.

Mobile Device Security:

With the rise of remote work, employees need to understand the risks associated with mobile devices. Educate them on the safe use of public Wi-Fi, the importance of keeping devices locked and secure, and installing antivirus software.

Physical Security:

Implement a 'clean-desk' policy to reduce the risk of unattended documents being stolen or copied. Ensure employees do not leave passwords visible on sticky notes, and remind them to secure their physical workspace, especially when working remotely.

Malware and Virus Protection:

Teach employees about the risks of malware and the importance of virus protection. Explain how to recognize potential malware indicators, such as unexplained errors or changes in computer behavior, and the steps to take if they suspect an infection.

Compliance and Regulations:

Keep employees up to date with changing regulations and compliance standards, such as GDPR, PCI DSS, ISO/IEC 27001 & 27002, and industry-specific requirements. Ensure they understand the consequences of non-compliance.

Social Media Usage:

Educate employees on protecting their privacy and the company's information when using social media. Discuss the risks of oversharing and how malicious actors can leverage this information.

Removable Media:

Cover the safe use of removable media, such as USB drives, in the workplace. Explain the risks, including lost or stolen devices, malware infections, and copyright infringement.

Remember, security awareness training should be tailored to the specific needs of your organization and combined with technical measures to create a robust cybersecurity strategy.

Frequently asked questions