CVE intelligenceCISA KEVRansomware use

CVE-2023-27997

Fortinet FortiOS and FortiProxy SSL-VPN Heap-Based Buffer Overflow Vulnerability

Published Jun 13, 2023Sources checked Sep 12, 2026

9.8CRITICALCVSS out of 10

What this means

Actively exploited

CISA lists CVE-2023-27997 in its Known Exploited Vulnerabilities catalog, which means exploitation has been observed. The entry applies to Fortinet FortiOS and FortiProxy SSL-VPN.

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CISA KEVListedObserved exploitation

EPSS85.7%Estimated 30-day exploitation probability

Ransomware useReported by CISACISA KEV ransomware field

Threat actors1Source-linked actor relationships

Overview

What is CVE-2023-27997?

A heap-based buffer overflow vulnerability [CWE-122] in FortiOS version 7.2.4 and below, version 7.0.11 and below, version 6.4.12 and below, version 6.0.16 and below and FortiProxy version 7.2.3 and below, version 7.0.9 and below, version 2.0.12 and below, version 1.2 all versions, version 1.1 all versions SSL-VPN may allow a remote attacker to execute arbitrary code or commands via specifically crafted requests.