CCE-95006-3| Platform: cpe:/o:debian:debian_linux:11.x, cpe:/o:ubuntu:ubuntu_linux:20.04, cpe:/o:ubuntu:ubuntu_linux:22.04, cpe:/o:ubuntu:ubuntu_linux:23.04 | Date: (C)2020-10-15 (M)2023-09-01 |
Setting icmp_ignore_bogus_error_responses to 1 prevents the kernel from logging bogus responses (RFC-1122 non-compliant) from broadcast reframes, keeping file systems from filling up with useless log messages.
Rationale:
Some routers (and some attackers) will send responses that violate RFC-1122 and attempt to fill up a log file system with many useless error messages.
Fix:
Set the net.ipv4.icmp_ignore_bogus_error_responses parameter to 1 in /etc/sysctl.conf and run sysctl -p command:
net.ipv4.icmp_ignore_bogus_error_responses=1
Modify active kernel parameters to match:
# /sbin/sysctl -w net.ipv4.icmp_ignore_bogus_error_responses=1
# /sbin/sysctl -w net.ipv4.route.flush=1
Parameter:
[yes/no]
Technical Mechanism:
Set the net.ipv4.icmp_ignore_bogus_error_responses parameter to 1 in /etc/sysctl.conf:
net.ipv4.icmp_ignore_bogus_error_responses=1
Modify active kernel parameters to match:
# /sbin/sysctl -w net.ipv4.icmp_ignore_bogus_error_responses=1
# /sbin/sysctl -w net.ipv4.route.flush=1
| CCSS Severity: | CCSS Metrics: |
| CCSS Score : 6.2 | Attack Vector: LOCAL |
| Exploit Score: 2.5 | Attack Complexity: LOW |
| Impact Score: 3.6 | Privileges Required: NONE |
| Severity: MEDIUM | User Interaction: NONE |
| Vector: AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N | Scope: UNCHANGED |
| | Confidentiality: HIGH |
| | Integrity: NONE |
| | Availability: NONE |
| | |
References: | Resource Id | Reference |
|---|
| SCAP Repo OVAL Definition | oval:org.secpod.oval:def:92374 |
| SCAP Repo OVAL Definition | oval:org.secpod.oval:def:66003 |
| SCAP Repo OVAL Definition | oval:org.secpod.oval:def:87330 |
| SCAP Repo OVAL Definition | oval:org.secpod.oval:def:85085 |
