The Juniper EX switch must be configured to permit authorized users to select a user session to capture.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-253952	JUEX-L2-000050	SV-253952r843889_rule		Medium

Description
Without the capability to select a user session to capture/record or view/hear, investigations into suspicious or harmful events would be hampered by the volume of information captured. The volume of information captured may also adversely impact the operation for the network. Session audits may include port mirroring, tracking websites visited, and recording information and/or file transfers.

STIG	Date
Juniper EX Series Switches Layer 2 Switch Security Technical Implementation Guide	2022-08-31

Details

Check Text ( C-57404r843887_chk )
Verify if the switch configuration has an analyzer to capture ingress and egress packets from any designated access interface for the purpose of monitoring a specific user session. Packet capture using the [edit forwarding-options analyzer ] configuration will only be present and enabled when actively monitoring sessions. If actively capturing packets, verify an analyzer is present. [edit forwarding-options] analyzer { { input { ingress { interface .; -or- interface irb.; } egress { interface .; -or- interface irb.; } } output { interface .; } } } Note: Simultaneously mirroring both ingress and egress traffic may exceed the output interface capacity. Packet mirroring consumes resources and should only be enabled when actively monitoring sessions. If active monitoring is not currently required, the lack of an analyzer, or the presence of an inactive (disabled) analyzer, is not a finding. If the switch is not configured to capture ingress and egress packets from a designated access interface, this is a finding.

Check Text ( C-57404r843887_chk )

Verify if the switch configuration has an analyzer to capture ingress and egress packets from any designated access interface for the purpose of monitoring a specific user session.

Packet capture using the [edit forwarding-options analyzer ] configuration will only be present and enabled when actively monitoring sessions.

If actively capturing packets, verify an analyzer is present.
[edit forwarding-options]
analyzer {
{
input {
ingress {
interface .;
-or-
interface irb.;
}
egress {
interface .;
-or-
interface irb.;
}
}
output {
interface .;
}
}
}
Note: Simultaneously mirroring both ingress and egress traffic may exceed the output interface capacity. Packet mirroring consumes resources and should only be enabled when actively monitoring sessions.

If active monitoring is not currently required, the lack of an analyzer, or the presence of an inactive (disabled) analyzer, is not a finding.

If the switch is not configured to capture ingress and egress packets from a designated access interface, this is a finding.

Fix Text (F-57355r843888_fix)
Enable the feature or configure the switch so that it is capable of capturing ingress and egress packets from any designated switch port for the purpose of monitoring a specific user session. To capture packets from the L2 interface ge-0/0/0 and forward out the L2 interface ge-0/0/1, configure the switch similarly to the example: set forwarding-options analyzer input ingress interface . -or- set forwarding-options analyzer input ingress interface irb. set forwarding-options analyzer input egress interface . -or- set forwarding-options analyzer input egress interface irb. set forwarding-options analyzer output interface .

Fix Text (F-57355r843888_fix)

Enable the feature or configure the switch so that it is capable of capturing ingress and egress packets from any designated switch port for the purpose of monitoring a specific user session.

To capture packets from the L2 interface ge-0/0/0 and forward out the L2 interface ge-0/0/1, configure the switch similarly to the example:

set forwarding-options analyzer input ingress interface .
-or-
set forwarding-options analyzer input ingress interface irb.

set forwarding-options analyzer input egress interface .
-or-
set forwarding-options analyzer input egress interface irb.

set forwarding-options analyzer output interface .