Fortinet FortiWeb is vulnerable to a stack‑based buffer overflow (CWE‑121) and an out‑of‑bounds write (CWE‑787). The flaw allows a remote authenticated attacker who can bypass stack protection and ASLR to send crafted HTTP requests that will execute arbitrary code or commands. The potential impact is full compromise of the device, leading to a loss of confidentiality, integrity, and availability for any network services protected by that FortiWeb instance.

The vulnerability affects Fortinet FortiWeb appliances running version 8.0.0 through 8.0.2, 7.6.0 through 7.6.6, all 7.4 releases, all 7.2 releases, and 7.0.2 through 7.0.12. Any production or test environment with those firmware versions is susceptible.

The CVSS score is 5.9, indicating moderate severity. The EPSS score is less than 1%, showing a very low probability of exploitation in the general population. The vulnerability is not listed in the CISA KEV catalog. Attackers must be authenticated but can then bypass security controls; the likely vector is through maliciously crafted HTTP traffic sent to the Web application firewall over the network. Exploitation would require the attacker to have necessary privileges to log into the device and then send the crafted requests.