Input validation error in BIG-IP LTM - CVE-2020-27720
Published: December 17, 2020
Vulnerability identifier: #VU49077
CSH Severity: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2020-27720
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
BIG-IP LTM
BIG-IP LTM
Software vendor:
F5 Networks
F5 Networks
Description
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to insufficient validation of network traffic in CGNAT LSN when processing NAT66 traffic with Port Block Allocation (PBA) mode and SP-DAG enabled, and dag-ipv6-prefix-len configured with a value less than the default of 128. A remote attacker can pass specially crafted input and cause the Traffic Management Microkernel (TMM) to restart.
Remediation
Install updates from vendor's website.