PHTN-40-000068 The Photon operating system must be configured to use TCP syncookies.

Information

A TCP SYN flood attack can cause a Denial of Service (DOS) by filling a system's TCP connection table with connections in the SYN_RCVD state. Syncookies can be used to track a connection when a subsequent ACK is received, verifying the initiator is attempting a valid connection and is not a flood source. This feature is activated when a flood condition is detected and enables the system to continue servicing valid connection requests.

Satisfies: SRG-OS-000142-GPOS-00071, SRG-OS-000420-GPOS-00186

Solution

Navigate to and open:

/etc/sysctl.d/zz-stig-hardening.conf

Add or update the following line:

net.ipv4.tcp_syncookies = 1

At the command line, run the following command to load the new configuration:

# /sbin/sysctl --load /etc/sysctl.d/zz-stig-hardening.conf

Note: If the file zz-stig-hardening.conf does not exist, it must be created.

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_VMW_vSphere_8-0_Y24M08_STIG.zip

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-5, 800-53|SC-5(2), CAT|II, CCI|CCI-001095, CCI|CCI-002385, Rule-ID|SV-258829r958528_rule, STIG-ID|PHTN-40-000068, Vuln-ID|V-258829

Plugin: Unix

Control ID: f174cccb3bd40c1057d83d73dcc4fe0ae3fde3c3ca0b984f4780adebdf3aa622