New Fortinet's FortiNAC Vulnerability Exposes Networks to Code Execution Attacks

A external control of file name or path in Fortinet FortiNAC versions 9.4.0, 9.2.0 through 9.2.5, 9.1.0 through 9.1.7, 8.8.0 through 8.8.11, 8.7.0 through 8.7.6, 8.6.0 through 8.6.5, 8.5.0 through 8.5.4, 8.3.7 may allow an unauthenticated attacker to execute unauthorized code or commands via specifically crafted HTTP request.

CVE-2023-27997 is a heap-based buffer overflow (CWE-122, with associated out-of-bounds write CWE-787) in the SSL-VPN component of Fortinet FortiOS and FortiProxy, reachable by unauthenticated users. A remote attacker can trigger it with specially crafted requests to the SSL-VPN web interface, gaining the ability to execute arbitrary code or commands on the gateway. Full control of an edge VPN/firewall appliance enables credential theft, session hijacking, and pivoting into the protected network, which makes the bug attractive to ransomware operators. Any organization exposing the SSL-VPN portal on the affected FortiOS builds (7.2.4 and below, 7.0.11 and below, 6.4.12 and below, 6.0.16 and below) or FortiProxy builds (7.2.3 and below, 7.0.9 and below, 2.0.12 and below, and 1.1/1.2 all versions) is potentially exposed. The flaw is under active exploitation: CISA added it to the KEV on 2023-06-13 with known ransomware use, EPSS estimates an ~86% probability of exploitation within 30 days (100th percentile), and reporting indicates it was likely being exploited in the wild, with Fortinet also warning that some attackers retained access to FortiGate devices even after patching.

Do: Apply Fortinet's updates to all SSL-VPN-enabled FortiOS and FortiProxy appliances as required by the CISA KEV listing, upgrading each affected branch beyond the listed versions (end-of-life FortiProxy 1.1/1.2 requires migration to a supported release); if SSL-VPN is not needed, disable the web portal or restrict it to trusted source addresses. After patching, hunt for signs of compromise and rotate credentials and VPN-related secrets, since Fortinet warned that some attackers retained access to FortiGate devices post-patching.

Grafana is validating Azure AD accounts based on the email claim. On Azure AD, the profile email field is not unique and can be easily modified. This leads to account takeover and authentication bypass when Azure AD OAuth is configured with a multi-tenant app.

A deserialization of untrusted data in Fortinet FortiNAC below 7.2.1, below 9.4.3, below 9.2.8 and all earlier versions of 8.x allows attacker to execute unauthorized code or commands via specifically crafted request on inter-server communication port. Note FortiNAC versions 8.x will not be fixed.

A improper neutralization of special elements used in a command ('command injection') in Fortinet FortiNAC 7.2.1 and earlier, 9.4.3 and earlier allows attacker a limited, unauthorized file access via specifically crafted request in inter-server communication port.