4.2.6 Enable Bad Error Message Protection - net.ipv4.icmp_ignore_bogus_error_responses = 1

Information

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.

Solution

Set the net.ipv4.icmp_ignore_bogus_error_responses parameter to 1 in /etc/sysctl.conf:

net.ipv4.icmp_ignore_bogus_error_responses=1

Run the following commands to set the active kernel parameters:

# /sbin/sysctl -w net.ipv4.icmp_ignore_bogus_error_responses=1
# /sbin/sysctl -w net.ipv4.route.flush=1

Default Value:

OS Default: Yes

See Also

https://workbench.cisecurity.org/files/3096

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-7b., CSCv7|9.2

Plugin: Unix

Control ID: 8ffa72cd4f5ade4914c94b4d5ab0325b32bbde7867f095389bef0bf740d4612d