Browser security is growing in importance with the rise of remote work, the growing prevalence of cloud-based services, and the increase in online transactions. Businesses are more exposed than ever to cyber threats that use the browser as their entry point. Browser security is critical not only for protecting their systems and data, but also for safeguarding reputation and customer relationships.

There are two aspects to browser security. One is to ensure employees are using the internet responsibly and that, no matter their device or location, their browsers are secure against threats like malware, malicious redirects, and phishing. 

Another is to prevent unauthorized access and data loss when employees access sensitive applications. With many business applications now running in browsers – from banking portals to customer relationship management tools to collaboration platforms – browser-based threats pose a much greater risk. Without robust browser security, sensitive data could inadvertently leak, or malicious actors could gain unwarranted access to critical business applications. 

Ensuring browser security, therefore, is as much about protecting the confidentiality and integrity of data as it is about safeguarding the enterprise’s vital operations and services.

Top Browser Threats and How to Prevent Them

Weak Antivirus Software and Other Protections

Threat actors are devising increasingly sophisticated ways to breach antivirus software, firewalls, and other measures of protection. Many threat actors manage to sidestep these defenses without being detected.

You can implement web browsing proxies, content filtering, and email scanners, to prevent threats before they reach the user’s browser. To provide additional layers of protection, deploy browser security solutions, which can detect internal and external web threats.

Additionally, organizations should implement automated patching, to ensure browsers, operating systems and other software is always running the latest, most secure, version. Employee training is also essential, because it can help users avoid falling for phishing and other social engineering attacks, and reduce their exposure to threats.

Redirects and Pop-up Ads

Pop ups are commonly used by threat actors as a means to infect computers with malicious code. The pop up may try to coerce users into accessing unsafe web pages, or downloading malware. There are various techniques for forcing users to interact with the pop-up — attackers may create a popup that cannot be closed, or include a warning that will urge the user to download a malicious payload.

Another technique is malicious redirects — these take the user from a safe web page to a malicious page. The malicious page may use browser or operating system vulnerabilities to trigger a drive-by download, might announce a warning or a threat, to trick users into downloading malware, or may pretend to be a legitimate page requesting the user’s sensitive details.

How to prevent popup and ad blockers can be very effective in reducing the threat of these attack techniques. Content filtering solutions can add another layer of defense, preventing malicious content from being displayed to users in the first place. Web filtering can be deployed on the user’s device or at the enterprise level — for example by using a secure web gateway (SWG).

Browser Extensions and Plugins

Plugins and browser extensions help improve user experience and extend the functionality of websites. However, while some plugins are well made, others are poorly designed and introduce vulnerabilities into the site. There are also plugins that are deliberately created with malicious intent.

To prevent this type of threat, create a policy that restricts users from installing plugins and extensions, preferably using a list of allowed and restricted plugins. Another option is adopting centralized software whitelisting and blacklisting solutions—these can be applied to plugins as well, enabling a centrally-governed solution for unsafe plugins. 

Communication with DNS Servers

When a user types an address into a web browser, the browser connects to a DNS server to discover the IP address matching that address. The DNS server is responsible for redirecting the browser to the appropriate site, but attackers can subvert this connection through a variety of means, directing the browser to a malicious site instead.

To protect against DNS attacks, organizations should use a private DNS resolver and ensure it is secure. Another option is to use a secure hosted DNS service, ensuring the DNS provider has strong security and compliance measures.

Saved Passwords and Form Info

Passwords protect valuable information and access to systems and networks. If threat actors manage to steal or decipher passwords, they can use these credentials to gain unauthorized access to certain systems and databases, or the entire network. The problem is that many users create the same weak password for many accounts, and use their browser to save passwords in an unprotected way.

It is critical to educate users not to use the browser’s password saving feature, and if possible, to disable it. However, because users do need a way to remember and organize passwords, organizations should implement password management software with the appropriate security and access control features.

A stronger, more effective measure is multifactor authentication (MFA). You can provide more than one way for a user to authenticate—using a piece of information they know (like a password), something they possess (like a mobile device or security token), or a personal characteristic (for example, their voice or fingerprint).

Malicious File Downloads

Protecting a browser from malicious downloads involves several steps. First, users should never download files from untrusted sources. If a website looks suspicious, it’s best to avoid it altogether. Secondly, organizations should use a browser that offers download protection. This feature will alert users if they are about to download a potentially harmful file. Finally, as mentioned earlier, robust antivirus software can be a last line of defense, in the event that malware is downloaded to a user’s device.

Phishing Attacks

Phishing attacks are a common and dangerous browser threat. In a phishing attack, cybercriminals attempt to trick users into revealing sensitive information, such as your usernames, passwords, or credit card details. They do this by creating fake websites that imitate a legitimate one, such as a digital banking or email service, and trick users into entering their details.

To prevent phishing attacks, users should always check the URL of the website they are visiting, ensure it is the correct address and that it starts with ‘https’, which indicates that the site is secure. Also, users should never click on links in unsolicited emails or messages, as they may lead to phishing sites. Instead, they should type the address directly into the browser.

While these basic measures can prevent some phishing attacks, they might not be effective against more sophisticated threats. Organizations should evaluate email security solutions, which can protect even highly sophisticated and evasive phishing attacks.

Browser Hijacking

Browser hijacking occurs when a malicious program or script changes browser settings without the user’s consent. The hijacker might change the homepage, search engine, or add unwanted toolbars and extensions. In some cases, it might even redirect to malicious websites or display intrusive ads.

To prevent browser hijacking, users should be cautious when installing new software. Some programs may try to change browser settings or install additional software as part of their installation process. Organizations should set clear policies as to what software can be installed, and preferably enforce these guidelines using web filtering systems. 

When they do install new software, users should always choose the custom installation option and uncheck any boxes that allow unwanted changes. Also, they should regularly check browser settings and extensions to ensure nothing has been altered without their knowledge.

Cross-Site Scripting (XSS)

Cross-site scripting, also known as XSS, is another significant threat to browser security. In an XSS attack, malicious scripts are injected into trusted websites, which can then be used to steal sensitive information or even take control of a user’s device.

To protect against XSS attacks, it’s crucial to use a web browser that has strong built-in security features. Many modern browsers have security settings that can be adjusted to block or warn about suspected XSS attacks. 

Cookie Theft

Cookies are small files that websites store on a computer to remember the user’s preferences and track online activities. While cookies can enhance the online experience, they can also pose a threat to browser security. Cookie theft, or ‘cookie hijacking’, is a technique used by cybercriminals to steal cookies and use them to gain access to personal information.

To prevent cookie theft, users should regularly clear their cookies. This can be done through the browser’s settings. Additionally, users should always access websites over a secure connection (HTTPS), as this can make it more difficult for hackers to intercept cookies.

Also, users should be wary of public Wi-Fi networks. These networks are often unsecured and can be a hotbed for cookie theft. If they must use public Wi-Fi, it is important to use a virtual private network (VPN) to encrypt personal data and protect cookies.