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The IPS must block outbound Internet Control Message Protocol (ICMP) Destination Unreachable, Redirect, and Address Mask reply messages.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-206893SRG-NET-000273-IDPS-00198SV-206893r1137740_ruleCCI-001312medium
Description
ICMP messages are used to provide feedback about problems in the network. These messages are sent back to the sender to support diagnostics; however, some messages can also provide host information and network topology that may be exploited by an attacker. An IPS must be configured to "silently drop" the packet and not send an ICMP control message back to the source. In some cases, it may be necessary to direct the traffic to a null interface. Three ICMP messages are commonly used by attackers for network mapping: Destination Unreachable, Redirect, and Address Mask Reply. These responses must be blocked on external interfaces; however, blocking the Destination Unreachable response will prevent Path Maximum Transmission Unit Discovery (PMTUD), which relies on the response "ICMP Destination Unreachable--Fragmentation Needed but DF Bit Set". PMTUD is a useful function and should only be "broken" after careful consideration. An acceptable alternative to blocking all Destination Unreachable responses is to filter Destination Unreachable messages generated by the IPS to allow ICMP Destination Unreachable--Fragmentation Needed but DF Bit Set (Type 3, Code 4) and apply this filter to the external interfaces.
STIGDate
Intrusion Detection and Prevention Systems Security Requirements Guide2025-09-22

Related Frameworks

1 mapping across 3 frameworks
SCF0 mappings

No source states a mapping between these directly.

Also reachable in 3 hops (1) derived by us, not asserted by any source

Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.

TDA-19Error Handling
1.00
NIST 800-530 mappings

No source states a mapping between these directly.

Also reachable in 2 hops (19) derived by us, not asserted by any source

Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.

AC-17(1)Monitoring and Control
1.00
AC-6(9)Log Use of Privileged Functions
1.00
AU-10Non-repudiation
1.00
AU-12Audit Record Generation
1.00
AU-14(1)System Start-up
1.00
AU-3Content of Audit Records
1.00
AU-3(1)Additional Audit Information
1.00
AU-9Protection of Audit Information
1.00
CM-3(5)Automated Security Response
1.00
CM-5(1)Automated Access Enforcement and Audit Records
1.00

+9 more (top 10 by confidence shown)

CCI1 mapping
CCI-001312
1.00

Details

Check Text (C-206893r1137740_chk)

If the device being reviewed is an IDS, this is not applicable. Verify the IPS blocks outbound ICMP Destination Unreachable, Redirect, and Address Mask reply messages. If the IPS does not block outbound ICMP Destination Unreachable, Redirect, and Address Mask reply messages, this is a finding.

Fix Text (F-7147r1137739_fix)

Configure the IPS to block outbound ICMP Destination Unreachable, Redirect, and Address Mask reply messages. An acceptable alternative to blocking all Destination Unreachable responses is to filter Destination Unreachable messages generated by the firewall implementation to allow ICMP Destination Unreachable-- Fragmentation Needed but DF Bit Set (Type 3, Code 4) and apply this filter to the external interfaces.