CCE-92637-8| Platform: cpe:/o:ubuntu:ubuntu_linux:18.04 | Date: (C)2019-11-07 (M)2023-07-04 |
The net.ipv4.ip_forward flag is used to tell the server whether it can forward packets or not. If the server is not to be used as a router, set the flag to 0.
Rationale:
Setting the flag to 0 ensures that a server with multiple interfaces (for example, a hard proxy), will never be able to forward packets, and therefore, never serve as a router.
Parameter:
[no/yes]
Technical Mechanism:
Set the net.ipv4.ip_forward parameter to 0 in /etc/sysctl.conf:
net.ipv4.ip_forward=0
Modify active kernel parameters to match:
# /sbin/sysctl -w net.ipv4.ip_forward=0
# /sbin/sysctl -w net.ipv4.route.flush=1
| CCSS Severity: | CCSS Metrics: |
| CCSS Score : 8.8 | Attack Vector: NETWORK |
| Exploit Score: 2.8 | Attack Complexity: LOW |
| Impact Score: 5.9 | Privileges Required: NONE |
| Severity: HIGH | User Interaction: REQUIRED |
| Vector: AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H | Scope: UNCHANGED |
| | Confidentiality: HIGH |
| | Integrity: HIGH |
| | Availability: HIGH |
| | |
References: | Resource Id | Reference |
|---|
| SCAP Repo OVAL Definition | oval:org.secpod.oval:def:51236 |
