AlmaLinux OS 9 must force a frequent session key renegotiation for SSH connections to the server.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-269120ALMA-09-003650SV-269120r1050610_ruleCCI-000068medium
Description
Without confidentiality protection mechanisms, unauthorized individuals may gain access to sensitive information via a remote access session. Remote access is access to DOD nonpublic information systems by an authorized user (or an information system) communicating through an external, nonorganization-controlled network. Remote access methods include, for example, dial-up, broadband, and wireless. Encryption provides a means to secure the remote connection to prevent unauthorized access to the data traversing the remote access connection (e.g., RDP), thereby providing a degree of confidentiality. The encryption strength of a mechanism is selected based on the security categorization of the information. Session key regeneration limits the chances of a session key becoming compromised.
STIGDate
Cloud Linux AlmaLinux OS 9 Security Technical Implementation Guide2026-02-27

Related Frameworks

3 paths across 3 frameworks
NIST 800-531 mapping
  • DISA · V1R6 · disa_xccdf · related
  • DISA · 2025-01-23 · disa_cci_list · equivalent
NIST 800-1711 mapping
3.1.13
1.00
  • DISA · V1R6 · disa_xccdf · related
  • DISA · 2025-01-23 · disa_cci_list · equivalent
  • NIST · Rev 2 (Feb 2020, errata Jan 2021) · nist_800_171_app_d · equivalent
CCI1 mapping
CCI-000068
1.00
  • DISA · V1R6 · disa_xccdf · related

Details

Check Text (C-269120r1050610_chk)

Verify the SSH server is configured to force frequent session key renegotiation with the following command: $ sshd -T | grep rekeylimit rekeylimit 1073741824 3600 If "RekeyLimit" does not have a maximum data amount and maximum time defined, this is a finding.

Fix Text (F-73052r1049131_fix)

Configure AlmaLinux OS 9 to force a frequent session key renegotiation for SSH connections to the server by running the following command: $ echo "RekeyLimit 1G 1h" > /etc/ssh/sshd_config.d/40-rekeylimit.conf