Check: PHTN-67-000104
VMware vSphere 6.7 Photon OS STIG:
PHTN-67-000104
(in versions v1 r6 through v1 r1)
Title
The Photon operating system must not forward IPv4 or IPv6 source-routed packets. (Cat II impact)
Discussion
Source routing is an Internet Protocol (IP) mechanism that allows an IP packet to carry information, a list of addresses, which tells a router the path the packet must take. There is also an option to record the hops as the route is traversed. The list of hops taken, the "route record", provides the destination with a return path to the source. This allows the source (the sending host) to specify the route, loosely or strictly, ignoring the routing tables of some or all of the routers. It can allow a user to redirect network traffic for malicious purposes and should therefore be disabled.
Check Content
At the command line, execute the following command: # /sbin/sysctl -a --pattern "net.ipv[4|6].conf.(all|default|eth.*).accept_source_route" Expected result: net.ipv4.conf.all.accept_source_route = 0 net.ipv4.conf.default.accept_source_route = 0 net.ipv4.conf.eth0.accept_source_route = 0 net.ipv6.conf.all.accept_source_route = 0 net.ipv6.conf.default.accept_source_route = 0 net.ipv6.conf.eth0.accept_source_route = 0 If the output does not match the expected result, this is a finding. Note: The number of "ethx" lines returned is dependent on the number of interfaces. Every "ethx" entry must be set to "0".
Fix Text
Open /etc/sysctl.conf with a text editor. Add or update the following lines: net.ipv4.conf.all.accept_source_route = 0 net.ipv4.conf.default.accept_source_route = 0 net.ipv4.conf.eth0.accept_source_route = 0 net.ipv6.conf.all.accept_source_route = 0 net.ipv6.conf.default.accept_source_route = 0 net.ipv6.conf.eth0.accept_source_route = 0 Run the following command to load the new setting: # /sbin/sysctl --load
Additional Identifiers
Rule ID: SV-239175r816656_rule
Vulnerability ID: V-239175
Group Title: SRG-OS-000480-GPOS-00227
Expert Comments
CCIs
Number | Definition |
---|---|
CCI-000366 |
The organization implements the security configuration settings. |
Controls
Number | Title |
---|---|
CM-6 |
Configuration Settings |