Illustrate the primary security risks involved in using a web-based wallet and propose specific mitigation strategies to minimize these vulnerabilities.

Web-based wallets, also known as online wallets or hosted wallets, offer a convenient way to access cryptocurrencies through a web browser. However, this convenience comes with significant security risks compared to other wallet types. The primary vulnerabilities of web-based wallets stem from the fact that they rely on third-party servers to store private keys and manage transactions, making them attractive targets for cyberattacks.

Here are the primary security risks involved:

1. Server-Side Vulnerabilities: The most significant risk is the vulnerability of the web wallet provider's servers. If the provider's servers are hacked, the attackers may gain access to all the private keys stored on their systems. This can result in massive theft of user funds. For example, a sophisticated SQL injection attack could exploit vulnerabilities in the provider's database, leading to the exposure of countless private keys. This risk is somewhat mitigated if the wallet provider implements secure server infrastructure, but the user is still relying on the providers security posture. This is an important risk to consider.

2. Phishing Attacks: Users are frequently targeted by phishing attacks where malicious actors create fake websites that mimic legitimate web-based wallet interfaces. These phishing sites trick users into entering their credentials, including private keys or passwords, allowing the attackers to gain control of their wallets. For example, a user might receive an email that looks like it’s from their wallet provider, urging them to log in to verify their account on a link, however it directs to a fake site controlled by the attacker.

3. Man-in-the-Middle Attacks: During communication between a user's browser and the web wallet server, a malicious actor could intercept and alter the data in transit using man-in-the-middle techniques. This could involve modifying transaction details or even injecting malicious code to steal private keys as the user enters them. For example, a hacker could position themselves in between your browser and the wallet's server on an unsecured network and alter the destination address when you submit a transaction.

4. Browser Extensions and Malware: Web-based wallets are often accessed through web browsers. Malicious browser extensions or malware on the user's computer could intercept keystrokes or steal login credentials. A keylogger, for example, could record every keystroke entered on a webpage, allowing a hacker to capture private keys or seed phrases as they are entered into a web-based wallet form. This is common in targeted attacks.

5. Lack of Control: With a web-based wallet, users do not have full control over their private keys. The wallet provider holds the keys, placing trust in their security practices. This dependence creates a single point of failure. If the provider becomes insolvent, is compromised, or is shut down, users could lose access to their funds. Also, it's common for these wallets to have centralized systems which goes against the decentralization principles that most crypto enthusiasts value.

6. Weak Security Practices: Some web-based wallet providers might not follow robust security practices. They could fail to implement proper encryption, regular security audits, or strong authentication mechanisms, leading to vulnerabilities that hackers can exploit. This is often true with smaller providers with less funds to invest into top security. The security of the funds depends on the security of the platform it resides on.

Mitigation Strategies:

1. Enable Two-Factor Authentication (2FA): Always enable 2FA (or MFA) whenever possible. This adds an extra layer of security by requiring a second verification factor, such as a code from a mobile app, in addition to your password. This dramatically reduces the impact of compromised credentials from a phishing attack.

2. Use Strong and Unique Passwords: Create strong and unique passwords for each web-based wallet and avoid reusing passwords from other accounts. Use a password manager to generate and store complex passwords and seed phrases.

3. Verify Website Authenticity: Always double-check the URL of the web wallet to ensure you are on the correct site. Look for the padlock icon in the address bar, indicating a secure connection. Avoid clicking links in emails or other messages and always manually type the website address into your browser. This protects against phishing.

4. Secure Your Computer: Keep your operating system and browser up to date with the latest security patches. Install reputable anti-virus and anti-malware software, and perform regular scans. Avoid clicking on suspicious links or downloading files from untrusted sources.

5. Use a Hardware Wallet: If the web-based wallet supports integration with a hardware wallet, use it. This adds a critical layer of security by keeping the private keys offline on the hardware device while still allowing for online access for transactions.

6. Limit Exposure: Avoid storing large amounts of cryptocurrency on web-based wallets. Use these wallets for smaller, more frequent transactions, and consider storing large amounts of cryptocurrency on cold storage solutions such as hardware wallets.

7. Research Wallet Providers: Choose reputable web-based wallet providers that have a track record of strong security practices, undergo regular security audits, and are transparent about their security measures. Read reviews, forums, and communities and make an informed decision before choosing a provider.

8. Be Mindful of Browser Extensions: Only install necessary and trusted browser extensions. Regularly review your browser extensions and remove any that you don't need or recognize. Make sure the extension is a legitimate product.

9. Network Security: Use secure, private networks and avoid public Wi-Fi, or use a Virtual Private Network (VPN) when transacting through web-based wallets. Malicious actors could intercept your information on a public network.

10. Regular Audits: Regularly check transaction history, make use of all security features offered by the wallet, and be vigilant.

By implementing these mitigation strategies, users can significantly reduce the risks associated with web-based wallets and better protect their cryptocurrency assets. However, it is important to understand that web-based wallets will inherently be more vulnerable than more secure solutions such as cold storage wallets.