Linux distributions
TMA-UBUNTU2004-3.2.1
Ensure dccp kernel module is not available
Description
The Datagram Congestion Control Protocol (DCCP) is a transport layer protocol that supports streaming media and telephony. DCCP provides a way to gain access to congestion control, without having to do it at the application layer, but does not provide in-sequence delivery.
How it is checked
Audit method: Shell command
m=dccp; found=$(find /lib/modules/$(uname -r)/kernel /usr/lib/modules/$(uname -r)/kernel -path "*/dccp*" 2>/dev/null | head -n1); if [ -z "$found" ]; then echo compliant; exit 0; fi; lsmod | awk '{print $1}' | grep -Fxq -- "${m//-/_}" && { echo "$m is loaded"; exit 0; }; cfg=$(modprobe --showconfig 2>/dev/null); printf '%s\n' "$cfg" | grep -Pq -- "^\h*blacklist\h+${m//-/_}\b" || { echo "$m is not blacklisted"; exit 0; }; printf '%s\n' "$cfg" | grep -Pq -- "^\h*install\h+${m//-/_}\h+(/usr)?/bin/(true|false)\b" || { echo "$m install is not disabled"; exit 0; }; echo compliant- Expected output
compliant
How it is fixed
Fix method: Guidance or infrastructure patch
Run the following to unload and disable the dccp kernel module. This can also be done by running the script included below. Run the following commands to unload the dccp kernel module: # modprobe -r dccp 2>/dev/null # rmmod dccp 2>/dev/null Perform the following to disable the dccp kernel module: Create a file ending in .conf with install dccp /bin/false in the /etc/modprobe.d/ directory Example: # printf '\n%s\n' "install dccp /bin/false" >> dccp.conf Create a file ending in .conf with blacklist dccp in the /etc/modprobe.d/ directory Example: # printf '\n%s\n' "blacklist dccp" >> dccp.conf Optional remediation script: This script will perform the above remediation as required by the system …
Properties
- Operating systems
- ubuntu-20.04
- Tags
- cis-convertedkernellinuxmodules
- Reference
- CIS Ubuntu Linux 20.04 LTS Benchmark v3.0.0 - 3.2.1
Check this host
Run this on a machine you are allowed to audit. The scan is read-only.
tmaegis scan --target linux --level 2