The tweet requests information about general WAF bypass techniques beyond using Shodan and censys alternate IP addresses. Since no specific payload or WAF vendor is mentioned in the tweet, I will explain some common concepts about WAF bypasses in simple language. Web Application Firewalls (WAFs) are security systems that protect websites from attacks such as SQL Injection, Cross-Site Scripting (XSS), Remote Code Execution (RCE), and others. Attackers try to bypass these WAFs to exploit vulnerabilities. Common bypass methods include:
1. Encoding Payloads: Changing the representation of attack code using URL encoding, Unicode encoding, Base64 encoding, etc., to evade pattern matching.
2. Using Alternate Syntax: Modifying the syntax of the attack payload to avoid detection, like using commenting, whitespace variations, or alternative function notations.
3. Splitting Payloads: Breaking malicious code into small parts that are reassembled at the target system.
4. Exploiting Whitelisted Paths or Parameters: Finding areas not well protected by WAF rules.
5. Timing Attacks and Behavioral Analysis Evasion: Sending payloads slowly or mimicking legitimate user behavior to avoid triggering WAF alarms.
6. Using Legitimate Services or APIs: Leveraging trusted external services to deliver malicious payloads indirectly.
Additionally, guessing or finding alternate IP addresses for the same service, as hinted in the tweet, is another method used to bypass IP-based WAF rules. These common strategies show that bypassing WAF is often about creative evasion using knowledge of the WAF’s detection techniques and the application’s behavior.
For more insights, check out the original tweet here: https://twitter.com/ShubhamVidhawan/status/1937573788847341675. And don’t forget to follow @ShubhamVidhawan for more exciting updates in the world of cybersecurity.