Title

The system must prevent local applications from generating source-routed packets. (Cat III impact)

Discussion

Source-routed packets allow the source of the packet to suggest that routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures.

Check Content

Determine the OS version you are currently securing. # uname –v Solaris 11, 11.1, 11.2, and 11.3 use IP Filter. To continue checking IP Filter, the IP Filter Management profile is required. Check the system for an IPF rule blocking outgoing source-routed packets. # ipfstat -o Examine the list for rules such as: block out log quick from any to any with opt lsrr block out log quick from any to any with opt ssrr If the listed rules do not block both lsrr and ssrr options, this is a finding. For Solaris 11.3 or newer that use Packet Filter, the Network Firewall Management rights profile is required. Ensure that IP Options are not in use: # pfctl -s rules | grep allow-opts If any output is returned, this is a finding.

Fix Text

The root role is required. # pfedit /etc/ipf/ipf.conf For Solaris 11, 11.1, 11.2, and 11.3 that use IP Filter dd rules to block outgoing source-routed packets, such as: block out log quick all with opt lsrr block out log quick all with opt ssrr Reload the IPF rules. # ipf -Fa -A -f /etc/ipf/ipf.conf For Solaris 11.3 or newer that use Packet Filter remove or modify any rules that include "allow-opts". Reload the Packet Filter rules: # svcadm refresh firewall:default

Additional Identifiers

Rule ID: SV-216394r603267_rule

Vulnerability ID: V-216394

Group Title: SRG-OS-000480

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.