CVE-2023-27997
Fortinet FortiOS and FortiProxy SSL-VPN Heap-Based Buffer Overflow Vulnerability
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 4 July 2023). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
Description
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.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 85.69% probability · 100th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Listed 13 June 2023 · due 4 July 2023 · used in ransomware campaigns
- Weakness
- CWE-122, CWE-787
- Affected
- fortinet/fortiproxy · fortinet/fortios
- Source
- psirt@fortinet.com
EPSS 85.7% since 30 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
CISA notes
Apply updates per vendor instructions. https://www.fortiguard.com/psirt/FG-IR-23-097; https://nvd.nist.gov/vuln/detail/CVE-2023-27997
References
- https://fortiguard.com/psirt/FG-IR-23-097Vendor Advisory
- https://fortiguard.com/psirt/FG-IR-23-097Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-27997US Government Resource
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.