Fortios
CVE-2023-40721
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization Format string safety
|
| Impact | CVSS score of 6.7 (MEDIUM). Attack characteristics: local attack vector, low complexity, high privileges required, no user interaction not required. EPSS exploitation probability: 0.02%. |
| Exploit ScenarioDerived | Successful exploitation could compromise the medium-severity affected system. |
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Alert meAnalysisAIv1 – Mar 28, 2026
A use of externally-controlled format string vulnerability [CWE-134] vulnerability in Fortinet allows a privileged attacker to execute arbitrary code or commands via specially crafted requests. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
Earlier versions of this analysis (1)
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Affects your stack
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Technical ContextAI · show details
This vulnerability is classified under CWE-134. A use of externally-controlled format string vulnerability [CWE-134] vulnerability in Fortinet allows a privileged attacker to execute arbitrary code or commands via specially crafted requests. Affected products include: Fortinet Fortios, Fortinet Fortiswitchmanager, Fortinet Fortiproxy, Fortinet Fortipam.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
A use of externally-controlled format string vulnerability [CWE-134] vulnerability in Fortinet allows a privileged attacker to execute arbitrary code or commands via specially crafted requests.
Executive ViewAI
CVE-2023-40721 presents notable security risk rated CVSS 6.7. Exploitation could compromise the security of affected deployments. Organizations should apply vendor updates when available and monitor for exploitation.
Apply vendor patch. If patching is delayed: restrict network access and enable monitoring.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.
Affected Products (CPE)CVE.org
An authentication bypass using an alternate path or channel [CWE-288] in Fortinet FortiOS version 7.2.0 through 7.2.1 an
FortiOS and FortiProxy contain an authentication bypass via the Node.js websocket module allowing unauthenticated remote
A out-of-bounds write in Fortinet FortiOS versions 7.4.0 through 7.4.2, 7.2.0 through 7.2.6, 7.0.0 through 7.0.13, 6.4.0
A heap-based buffer overflow vulnerability [CWE-122] in FortiOS version 7.2.4 and below, version 7.0.11 and below, versi
FortiOS SSL-VPN contains an improper authentication vulnerability that allows users to bypass two-factor authentication
Fortinet FortiAnalyzer before 5.0.12 and 5.2.x before 5.2.5; FortiSwitch 3.3.x before 3.3.3; FortiCache 3.0.x before 3.0
Buffer overflow in the Cookie parser in Fortinet FortiOS 4.x before 4.1.11, 4.2.x before 4.2.13, and 4.3.x before 4.3.9
Remote code execution in Fortinet FortiOS (6.4 through 7.6.3) and FortiSwitchManager (7.0.x/7.2.x) lets an attacker run
Path traversal vulnerability in Fortinet FortiOS, FortiProxy, FortiPAM, and FortiSwitchManager allows authenticated admi
Cross-site scripting (XSS) vulnerability in the sslvpn login page in Fortinet FortiOS 5.2.x before 5.2.3 allows remote a
FortiOS and FortiProxy contain an authentication bypass allowing unauthenticated attackers with knowledge of upstream/do
An Exposure of Sensitive Information to an Unauthorized Actor vulnerability [CWE-200] vulnerability in Fortinet FortiOS
GitHub PoC
Exploit-DB