TCP backlog queue sizes must be set appropriately.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-23741	GEN003601	SV-28639r2_rule		Medium

Description
To provide some mitigation to TCP DoS attacks, the TCP backlog queue sizes must be set to at least 1280 or in accordance with product-specific guidelines.

STIG	Date
SOLARIS 10 X86 SECURITY TECHNICAL IMPLEMENTATION GUIDE	2016-06-22

Details

Check Text ( C-28894r3_chk )
Determine the type of zone that you are currently securing. # zonename If the zone is not the global zone, determine if any interfaces are exclusive to the zone: # dladm show-link If the output indicates "insufficient privileges" then this requirement is not applicable. If the zone is the global zone or the non-global zone has exclusive interfaces determine the network settings. Procedure: # ndd /dev/tcp tcp_conn_req_max_q0 If the returned value is not 1280 or greater, this is a finding. Procedure: # ndd /dev/tcp tcp_conn_req_max_q If the returned value is not 1024, this is a finding.

Check Text ( C-28894r3_chk )

Determine the type of zone that you are currently securing.
# zonename

If the zone is not the global zone, determine if any interfaces are exclusive to the zone:
# dladm show-link

If the output indicates "insufficient privileges" then this requirement is not applicable.

If the zone is the global zone or the non-global zone has exclusive interfaces determine the network settings.

Procedure:
# ndd /dev/tcp tcp_conn_req_max_q0

If the returned value is not 1280 or greater, this is a finding.

Procedure:
# ndd /dev/tcp tcp_conn_req_max_q

If the returned value is not 1024, this is a finding.

Fix Text (F-25916r1_fix)
Procedure: # ndd -set /dev/tcp tcp_conn_req_max_q0 1280 # ndd -set /dev/tcp tcp_conn_req_max_q 1024 Ensure these commands are also present in system startup scripts.