Your Browser Is Not Secure

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Understanding browser vulnerabilities is crucial in addressing critical web security flaws such as improper input validation and access control. Exploitation techniques like Cross-site Scripting (XSS) and Cross-site Request Forgery (CSRF) using various vulnerabilities pose significant risks to data integrity and system functionality. Learning about common exploits and strategies will enhance browser security, which is essential for individuals and organizations aiming to bolster their cyber resilience against evolving threats.

Vulnerabilities in Browsers

In web security, several critical vulnerabilities demand attention, including improper input validation, improper access control. Such vulnerabilities can be exploited using Cross-site Scripting (XSS), Cross-site Request Forgery (CSRF), and code injection attacks. These vulnerabilities pose significant risks to data integrity and system functionality. Understanding and addressing these vulnerabilities are essential for effective cyber resilience.

Improper input validation refers to the failure to adequately check and sanitize user-supplied data before processing or displaying it on a website or application. This can lead to security vulnerabilities such as SQL injection and cross-site scripting attacks, where malicious actors can exploit these weaknesses to inject harmful code, compromise data, and disrupt system functionality. Proper input validation involves implementing measures such as escaping special characters, validating input formats, and ensuring that user data is sanitized to prevent potential security risks (Mozilla Developer, The Github Blog, Security Gladiators).

Improper access control occurs when a web application fails to adequately enforce what authenticated users are allowed to do or see. This vulnerability can allow users to access sensitive data they should not have access to, or perform actions beyond their authorized permissions, such as modifying data or executing administrative functions. The risks associated with improper access control are severe, ranging from data breaches to unauthorized operations that can have far-reaching consequences for an organization (Mach One Digital).

Cross-site scripting (XSS) is a type of web security vulnerability that involves injecting malicious scripts into web applications and executing them in the user’s browser. These scripts can be used by attackers to remotely control web applications, steal sensitive data like authentication cookies, redirect users to malicious websites, deface websites, or take over user sessions. XSS attacks can be reflected or persistent depending on how the injected scripts are returned to the browser (EC-Council, Mozilla Developer, The Github Blog).

Cross-site request forgery (CSRF) is a cyberattack where a malicious website exploits a user’s browser to send unauthorized requests to a legitimate site. This type of attack takes advantage of the trust placed in session IDs and the automatic behavior of browsers, leading users to unknowingly execute unwanted actions on a web application they are authenticated on, such as fund transfers or changes to personal information. CSRF attacks can impact users and websites significantly by exploiting the trust that the target site has for requests initiated by authenticated users, despite actually being initiated from elsewhere (Kryvets, The Github Blog).

A code injection attack is when a malicious actor inserts harmful logic or commands into an application, exploiting vulnerabilities in the application’s handling of user input. This can lead to unauthorized access, data breaches, data manipulation, and compromise of the application, its data, and connected servers (The Github Blog, Mach One Digital, Cypress Data Defense).

Identifying vulnerabilities and exploits in browsers involves understanding that attackers target flaws in the browser or the applications it uses to process web requests. This can include targeting applications like RealPlayer, QuickTime, or the victim’s antivirus program, along with submitting malicious Javascript requests such as cross-site scripting (XSS) or cross-site request forgery (XSRF) to the browser. Additionally, attackers can access a victim’s browsing history or clipboard contents, potentially compromising sensitive information like passwords or credit card numbers. Staying protected involves using the most recent major release of a browser and utilizing security features beyond incremental patches, as well as implementing phishing filters to reduce the chances of users visiting malicious sites (TechTarget, GeeksforGeeks).

Hacking Modern Browsers

Browser vulnerabilities can be leveraged by attackers through techniques such as inserting malicious code into a website’s content. This can lead to the execution of processes within the browser application in unintended ways. This can potentially grant access to the visitor’s machine. Once the attacker gains access, they can exploit known security vulnerabilities to gain privileged access to the system, enabling them to perform malicious activities on the machine or even the victim’s entire network. Additionally, attackers can target flaws in the browser or applications the browser calls to process web requests, access browsing history, clipboard contents, passwords, or credit card numbers, and exploit various web security vulnerabilities such as SQL injection, insecure wireless networks, and file download/upload vulnerabilities to steal sensitive data (Wikipedia, TechTarget, Cypress Data Defense).

Hackers may also use techniques like “drive-by downloads” where visiting a compromised site can automatically download and execute malicious code. Phishing emails containing exploit kits are another common tactic to target web browsers, exploiting unpatched vulnerabilities to deploy malware or steal data (Darkreading, TechTarget, CSO Online).

Such vulnerabilities have led to security breaches in various instances, such as the exploitation of a zero-day bug (CVE-2023–5217) in a Chrome software library by a commercial vendor to drop the Predator spyware tool on affected Android devices (Darkreading). These vulnerabilities can be exploited by attackers to gain control over the browser or the user’s system, leading to breaches for purposes like bypassing protections for displaying pop-up advertising, collecting personally identifiable information, website tracking, installing malware, and conducting man-in-the-browser attacks (Wikipedia). As an example, attackers accessed Avast’s internal network in 2019 by exploiting a temporary VPN account with a username and password that was left open and did not have 2FA, making it easy to access Avast’s computers (Splunk).

Mitigating Browser Exploits

Browser developers address and patch vulnerabilities primarily by regularly producing updates to their products that close off loopholes and security weaknesses. They also conduct research on security vulnerabilities to identify and fix them before they are exploited by hackers. Such research is conducted through in-depth studies that analyze the root causes of security vulnerabilities in browsers, including those discussed here. Additionally, concerns over browser attacks have led organizations to implement measures such as securing browser use, deploying controls for forced browser updates, removing suspicious extensions, and restricting non-corporate browser profiles to mitigate risks associated with browser vulnerabilities. Adversaries focus on uncovering vulnerabilities in main browser engines due to browser market consolidation, leading to the collection of sensitive information by browsers that hackers seek to exploit (Darkreading).

Users can enhance browser security by allowing automatic updates and adjusting browser settings to close off entry points that hackers could exploit. More specifically, the following are recommended:

• Adjusting network settings,
• clearing browser history,
• cached data, cookies,
• regularly erasing stored passwords and cookies, and
• enforcing multifactor authentication (MFA) on critical systems and services

Though out of the scope of this article, MFA is subject to it’s own security risks. It is worth knowing how hackers can specifically target MFA and 2FA systems, especially when they’re used in organizations. The article Exploiting MFA and 2FA provides the relevant information on that subject.

Furthermore, choosing a browser based on privacy and security features, using newer hardware for better encryption and security features, and following security principles such as using strong passwords and being vigilant of phishing attempts can help mitigate hackers (Comparitech, Darkreading, Russ Harvey Consulting).

In organizations and businesses, IT teams play a crucial role in securing browser vulnerabilities. IT teams should be responsible for a variety of things, including:

• Establishing organization-wide browser policies and training material
• Ensuring the establishment of secure browser settings, like managing pop-ups and auto-updates
• Approving all browser extensions and add-ons used within the organization
• Implementing threat detection and response solutions
• Ensuring remote-reboot for users when required.

All of these are essential in mitigating risks in browser securities (Darkreading, TechTarget, SentinelOne). Ultimately, the security of an organization is fully determined by the practices of its employees, and so regular training in various security measures and practices is just as important as any other mitigation factors.

References

• CSO Online. Exploit chains explained: How and why attackers target multiple vulnerabilities. Retrieved from https://www.csoonline.com/article/571799/exploit-chains-explained-how-and-why-attackers-target-multiple-vulnerabilities.html
• Comparitech. Browser security guide: Chrome, Firefox, Internet Explorer, Edge & Safari. Retrieved from https://www.comparitech.com/blog/vpn-privacy/browser-security-chrome-firefox-edge-safari/
• Cypress Data Defense. 6 Web Application Vulnerabilities and How to Prevent Them. Retrieved from https://cypressdatadefense.com/blog/web-application-vulnerabilities/
• Darkreading. Google Chrome Zero-Day Bug Under Attack, Allows Code Injection. Retrieved from https://www.darkreading.com/cloud-security/google-chrome-zero-day-bug-attack-code-injection
• Darkreading Why Browser Vulnerabilities Are a Serious Threat — and How to Minimize Your Risk. Retrieved from https://www.darkreading.com/cyberattacks-data-breaches/why-browser-vulnerabilities-are-a-serious-threat-and-how-to-minimize-your-risk
• EC-Council. Web Application Security Best Practices | Threat Mitigation. Retrieved from https://www.eccouncil.org/cybersecurity-exchange/application-security/threat-mitigation-strategies-for-securing-web-applications/
• GeeksforGeeks. What are browser vulnerabilities and how to stay protected? — GeeksforGeeks. Retrieved from https://www.geeksforgeeks.org/what-are-browser-vulnerabilities-and-how-to-stay-protected/
• The Github Blog. Today’s most common security vulnerabilities explained. Retrieved from https://github.blog/2022-05-06-todays-most-common-security-vulnerabilities-explained/
• Mach One Digital. Secure Coding: Understanding and Mitigating the OWASP Top 10 Vulnerabilities. Retrieved from https://www.machonedigital.com/blog/secure-coding-understanding-and-mitigating-the-owasp-top-10-vulnerabilities
• Mozilla Developer. Security on the web. Retrieved from https://developer.mozilla.org/en-US/docs/Web/Security
• Russ Harvey Consulting. Web Security: Vulnerabilities in Internet software. Retrieved from https://www.russharvey.bc.ca/resources/websecurity.html
• Security Gladiators. Behind the URL: Exploring Common Browser-Based Network Attacks. Retrieved from https://securitygladiators.com/threat/hacking/browser-based-network-attacks/
• SentinelOne. Beyond the WebP Flaw | An In-depth Look at 2023’s Browser Security Challenges. Retrieved from https://www.sentinelone.com/blog/beyond-the-webp-flaw-an-in-depth-look-at-2023s-browser-security-challenges/
• Splunk. Security Breach Types: Top 10 (with Real-World Examples). Retrieved from https://www.splunk.com/en_us/blog/learn/security-breach-types.html
• TechTarget. How to avoid attacks that exploit a Web browser vulnerability. Retrieved from https://www.techtarget.com/searchsecurity/tip/How-to-avoid-attacks-that-exploit-a-Web-browser-vulnerability
• TechTarget. What are the basics of a Web browser exploit?. Retrieved from https://www.techtarget.com/searchsecurity/answer/What-are-the-basics-of-a-Web-browser-exploit
• Wikipedia. Browser security. Retrieved from https://en.wikipedia.org/wiki/Browser_security