SB2023121504 - Security restrictions bypass in FortiOS IPS Engine
Published: December 15, 2023
Security Bulletin ID
SB2023121504
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Interpretation Conflict (CVE-ID: CVE-2023-40718)
CWE-ID: CWE-436 - Interpretation Conflict
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to bypass implemented security policies.
The vulnerability exists due to an interpretation conflict when handling custom TCP flags. A remote attacker can send specially crafted TCP packets to evade NGFW policies or IPS Engine protection.
Remediation
Install update from vendor's website.