The RHEL 8 operating system must implement DoD-approved TLS encryption in the OpenSSL package.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-230255	RHEL-08-010294	SV-230255r877394_rule		Medium

Description
Without cryptographic integrity protections, information can be altered by unauthorized users without detection. Remote access (e.g., RDP) is access to DoD nonpublic information systems by an authorized user (or an information system) communicating through an external, non-organization-controlled network. Remote access methods include, for example, dial-up, broadband, and wireless. Cryptographic mechanisms used for protecting the integrity of information include, for example, signed hash functions using asymmetric cryptography enabling distribution of the public key to verify the hash information while maintaining the confidentiality of the secret key used to generate the hash. RHEL 8 incorporates system-wide crypto policies by default. The employed algorithms can be viewed in the /etc/crypto-policies/back-ends/openssl.config file. Satisfies: SRG-OS-000250-GPOS-00093, SRG-OS-000393-GPOS-00173, SRG-OS-000394-GPOS-00174, SRG-OS-000125-GPOS-00065

Description

Without cryptographic integrity protections, information can be altered by unauthorized users without detection. Remote access (e.g., RDP) is access to DoD nonpublic information systems by an authorized user (or an information system) communicating through an external, non-organization-controlled network. Remote access methods include, for example, dial-up, broadband, and wireless. Cryptographic mechanisms used for protecting the integrity of information include, for example, signed hash functions using asymmetric cryptography enabling distribution of the public key to verify the hash information while maintaining the confidentiality of the secret key used to generate the hash. RHEL 8 incorporates system-wide crypto policies by default. The employed algorithms can be viewed in the /etc/crypto-policies/back-ends/openssl.config file. Satisfies: SRG-OS-000250-GPOS-00093, SRG-OS-000393-GPOS-00173, SRG-OS-000394-GPOS-00174, SRG-OS-000125-GPOS-00065

STIG	Date
Red Hat Enterprise Linux 8 Security Technical Implementation Guide	2022-12-06

Details

Check Text ( C-32924r809380_chk )
Verify the OpenSSL library is configured to use only DoD-approved TLS encryption: For versions prior to crypto-policies-20210617-1.gitc776d3e.el8.noarch: $ sudo grep -i MinProtocol /etc/crypto-policies/back-ends/opensslcnf.config MinProtocol = TLSv1.2 If the "MinProtocol" is set to anything older than "TLSv1.2", this is a finding. For version crypto-policies-20210617-1.gitc776d3e.el8.noarch and newer: $ sudo grep -i MinProtocol /etc/crypto-policies/back-ends/opensslcnf.config TLS.MinProtocol = TLSv1.2 DTLS.MinProtocol = DTLSv1.2 If the "TLS.MinProtocol" is set to anything older than "TLSv1.2" or the "DTLS.MinProtocol" is set to anything older than DTLSv1.2, this is a finding.

Check Text ( C-32924r809380_chk )

Verify the OpenSSL library is configured to use only DoD-approved TLS encryption:

For versions prior to crypto-policies-20210617-1.gitc776d3e.el8.noarch:

$ sudo grep -i MinProtocol /etc/crypto-policies/back-ends/opensslcnf.config

MinProtocol = TLSv1.2

If the "MinProtocol" is set to anything older than "TLSv1.2", this is a finding.

For version crypto-policies-20210617-1.gitc776d3e.el8.noarch and newer:

$ sudo grep -i MinProtocol /etc/crypto-policies/back-ends/opensslcnf.config

TLS.MinProtocol = TLSv1.2
DTLS.MinProtocol = DTLSv1.2

If the "TLS.MinProtocol" is set to anything older than "TLSv1.2" or the "DTLS.MinProtocol" is set to anything older than DTLSv1.2, this is a finding.

Fix Text (F-32899r809381_fix)
Configure the RHEL 8 OpenSSL library to use only DoD-approved TLS encryption by editing the following line in the "/etc/crypto-policies/back-ends/opensslcnf.config" file: For versions prior to crypto-policies-20210617-1.gitc776d3e.el8.noarch: MinProtocol = TLSv1.2 For version crypto-policies-20210617-1.gitc776d3e.el8.noarch and newer: TLS.MinProtocol = TLSv1.2 DTLS.MinProtocol = DTLSv1.2 A reboot is required for the changes to take effect.

Fix Text (F-32899r809381_fix)

Configure the RHEL 8 OpenSSL library to use only DoD-approved TLS encryption by editing the following line in the "/etc/crypto-policies/back-ends/opensslcnf.config" file:

For versions prior to crypto-policies-20210617-1.gitc776d3e.el8.noarch:
MinProtocol = TLSv1.2

For version crypto-policies-20210617-1.gitc776d3e.el8.noarch and newer:
TLS.MinProtocol = TLSv1.2
DTLS.MinProtocol = DTLSv1.2
A reboot is required for the changes to take effect.