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RHEL 10 must be configured so that the Secure Shell (SSH) daemon disables remote X connections for interactive users.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-281258RHEL-10-700550SV-281258r1184758_ruleCCI-002696medium
Description
When X11 forwarding is enabled, there may be additional exposure to the server and client displays if the sshd proxy display is configured to listen on the wildcard address. By default, sshd binds the forwarding server to the loopback address and sets the hostname part of the DISPLAY environment variable to localhost. This prevents remote hosts from connecting to the proxy display. OpenSSH uses the first occurrence of a keyword it sees, and drop-in files are read in lexicographical order at the start of the configuration. Red Hat recommends using drop-in files rather than changing base configuration files.
STIGDate
Red Hat Enterprise Linux 10 Security Technical Implementation Guide2026-03-11

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.

CHG-06Control Functionality Verification
0.50
NIST 800-530 mappings

No source states a mapping between these directly.

Also reachable in 2 hops (14) 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-3(4)Discretionary Access Control
1.00
AU-12Audit Record Generation
1.00
AU-3Content of Audit Records
1.00
AU-3(1)Additional Audit Information
1.00
AU-8Time Stamps
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
CM-5(6)Limit Library Privileges
1.00
CM-7(2)Prevent Program Execution
1.00

+4 more (top 10 by confidence shown)

CCI1 mapping
CCI-002696
1.00

Details

Check Text (C-281258r1184758_chk)

Verify RHEL 10 SSH daemons do not allow X11Forwarding with the following command: $ sudo /usr/sbin/sshd -dd 2>&1 | awk '/filename/ {print $4}' | tr -d '\r' | tr '\n' ' ' | xargs sudo grep -iH '^\s*x11forwarding' /etc/ssh/sshd_config.d/10-stig.conf:X11forwarding no /etc/ssh/sshd_config.d/50-redhat.conf:X11Forwarding yes Verify the runtime setting with the following command: $ sudo sshd -T | grep -i x11forwarding x11forwarding no If the "X11forwarding" keyword is not set to "no" in a drop-in that lexicographically precedes 50-redhat.conf, or if no output is returned, and X11 forwarding is not documented with the information system security officer as an operational requirement, this is a finding.

Fix Text (F-85724r1166725_fix)

Configure RHEL 10 SSH daemons to not allow X11 forwarding. In "/etc/ssh/sshd_config.d", create a drop file that will lexicographically precede 50-redhat.conf and add the following line: X11forwarding no Restart the SSH service with the following command for the changes to take effect: $ sudo systemctl restart sshd.service