# CVE-2023-27997: Fortinet FortiOS and FortiProxy SSL-VPN Heap-Based Buffer Overflow Vulnerability

- Exploited (CISA KEV): yes, added 2023-06-13, known ransomware use
- Published: 2023-06-13
- CVSS: 9.2 CRITICAL (v3.1)
- EPSS: 85.7% (100th percentile)
- CWE: CWE-122

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.

## Edge WAF coverage (claimed by vendors, not measured)

| Vendor | Status | First rule | Days after publication |
|---|---|---|---|
| Cloudflare | Before feed history | — | — |
| AWS | No public claim | — | — |
| Microsoft Azure | No public claim | — | — |
| Google Cloud | Before feed history | — | — |
| Fastly | Before feed history | — | — |
| F5 | Rule published | 2023-07-11 | 28 |
| Akamai | No public source | — | — |
| OWASP CRS | No public claim | — | — |

### F5

- 2023-07-11 · new · rule 200011093
  > Added: signature 200011093 "Fortinet SSL VPN Buffer Overflow" (Buffer Overflow, risk High), systems: Other Web Server. References: CVE-2023-27997.
  Source: https://docs.cloud.f5.com/docs-v2/platform/changelogs/security-details-changelog
- 2023-08-08 · new · rule 200011093
  > Added: signature 200011093 "Fortinet SSL VPN Buffer Overflow" (Buffer Overflow, risk High), systems: Other Web Server. References: CVE-2023-27997.
  Source: https://docs.cloud.f5.com/docs-v2/platform/changelogs/security-details-changelog

"No public claim" means no vendor statement names this CVE; "Before feed history" means the CVE is older than the vendor feed. In both cases generic rules may still block it.

HTML: https://cve.vigilbase.com/cve/CVE-2023-27997 · JSON: https://cve.vigilbase.com/api/v1/cves/CVE-2023-27997