SB2023090707 - Improper handling of IPv6 fragment headers in FreeBSD pf
Published: September 7, 2023
Security Bulletin ID
SB2023090707
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) Security features bypass (CVE-ID: CVE-2023-4809)
CWE-ID: CWE-254 - Security Features
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to bypass implemented firewall rules.
The vulnerability exists due to improper handling of multiple IPv6 fragment headers in pf implementation with "scrub fragment reassemble" rule. A remote attacker can send specially crafted IPv6 packets to the system and bypass implemented filtration rules.
Remediation
Install update from vendor's website.