#VU83985 Input validation error in FreeBSD - CVE-2023-6534
Published: December 7, 2023
Vulnerability identifier: #VU83985
Vulnerability risk: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2023-6534
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
FreeBSD
FreeBSD
Software vendor:
FreeBSD Foundation
FreeBSD Foundation
Description
The vulnerability allows a remote attacker to perform spoofing attack.
The vulnerability exists due to missing validation of TCP sequence numbers on inbound packets in pf(4). A remote attacker can guess the connection's port numbers and inject packets into existing TCP streams, resulting in spoofing attack.
This could be used to implement a denial-of-service attack for hosts behind the firewall, for example by sending TCP RST packets to the host.
Remediation
Install updates from vendor's website.