December 12, 2022
Claroty experts created a generic method for circumventing a variety of leading manufacturers’ web application firewalls (WAF).
The technique, developed by Claroty’s threat research team Team82, is generic, which means it can be used against web application firewalls (WAFs) from various vendors. The technique has been successfully tested against products from Amazon Web Services, Cloudflare, F5, Imperva, and Palo Alto Networks.
WAFs act as a security guardrail against malicious external HTTP(S) traffic, allowing an attacker with the ability to breach the barrier to gain initial access to a target environment for further post-exploitation. Claroty’s bypass mechanism relies on WAFs’ lack of JSON support to craft rogue SQL injection payloads that include JSON syntax to avoid detection.
The vulnerability was reported to be exploitable against the on-premises version, but the Amazon Web Services (AWS) WAF blocked all attempts to exploit it against the cloud version by flagging the SQL injection payload as malicious.
The bypass technique could be used in a number of different attacks. WAFs are used to protect not only web applications, but also APIs and cloud-based management platforms, as Claroty mentioned. Attackers could use the bypass to gain access to backend databases and then exfiltrate data through compromised servers or cloud instances by exploiting additional flaws.
The sources for this piece include an article in TheHackerNews.
