The operating system must request and perform data origin authentication verification and data integrity verification on the name/address resolution responses the system receives from authoritative sources.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-221865	OL07-00-040480	SV-221865r505922_rule		Medium

Description
If data origin authentication and data integrity verification are not performed, the resultant response could be forged, it may have come from a poisoned cache, the packets could have been intercepted without the resolver's knowledge, or resource records could have been removed, which would result in query failure or DoS. Data origin authentication must be performed to thwart these types of attacks. Each client of name resolution services either performs this validation on its own or has authenticated channels to trusted validation providers. Information systems that provide name and address resolution services for local clients include, for example, recursive resolving or caching Domain Name System (DNS) servers. DNS client resolvers either perform validation of DNSSEC signatures, or clients use authenticated channels to recursive resolvers that perform such validations. Information systems that use technologies other than the DNS to map between host/service names and network addresses provide other means to enable clients to verify the authenticity of response data. This is not applicable if DNSSEC is not implemented on the local network. Satisfies: SRG-OS-000399-GPOS-00178, SRG-OS-000400-GPOS-00179, SRG-OS-000401-GPOS-00180, SRG-OS-000402-GPOS-00181

Description

If data origin authentication and data integrity verification are not performed, the resultant response could be forged, it may have come from a poisoned cache, the packets could have been intercepted without the resolver's knowledge, or resource records could have been removed, which would result in query failure or DoS. Data origin authentication must be performed to thwart these types of attacks. Each client of name resolution services either performs this validation on its own or has authenticated channels to trusted validation providers. Information systems that provide name and address resolution services for local clients include, for example, recursive resolving or caching Domain Name System (DNS) servers. DNS client resolvers either perform validation of DNSSEC signatures, or clients use authenticated channels to recursive resolvers that perform such validations. Information systems that use technologies other than the DNS to map between host/service names and network addresses provide other means to enable clients to verify the authenticity of response data. This is not applicable if DNSSEC is not implemented on the local network. Satisfies: SRG-OS-000399-GPOS-00178, SRG-OS-000400-GPOS-00179, SRG-OS-000401-GPOS-00180, SRG-OS-000402-GPOS-00181

STIG	Date
Oracle Linux 7 Security Technical Implementation Guide	2020-09-10

Details

Check Text ( C-23580r419667_chk )
Verify the operating system implements DNSSEC to protect the integrity of name/address resolution. Determine if the package "unbound" is installed via the following command: # yum info unbound If unbound is not installed, this is a finding. If "unbound" is installed, determine whether the unbound daemon is running; enter the following command: # systemctl status unbound \| grep Active If the output does not indicate the daemon is "active", this is a finding.

Check Text ( C-23580r419667_chk )

Verify the operating system implements DNSSEC to protect the integrity of name/address resolution.

Determine if the package "unbound" is installed via the following command:
# yum info unbound

If unbound is not installed, this is a finding.

If "unbound" is installed, determine whether the unbound daemon is running; enter the following command:
# systemctl status unbound | grep Active

If the output does not indicate the daemon is "active", this is a finding.

Fix Text (F-23569r419668_fix)
Configure the operating system to implement DNSSEC to protect the integrity of name/address resolution. Install the unbound package: # yum install unbound To ensure unbound starts up every time the system boots, run the following command: # systemctl enable unbound