The Ubuntu operating system for PKI-based authentication, must implement a local cache of revocation data in case of the inability to access revocation information via the network.
An XCCDF Rule
Description
Without configuring a local cache of revocation data, there is the potential to allow access to users who are no longer authorized (users with revoked certificates).
- ID
- SV-238233r1015151_rule
- Version
- UBTU-20-010066
- Severity
- Medium
- References
- Updated
Remediation Templates
A Manual Procedure
Configure the Ubuntu operating system, for PKI-based authentication, to use local revocation data when unable to access the network to obtain it remotely.
Add or update the "cert_policy" option in "/etc/pam_pkcs11/pam_pkcs11.conf" to include "crl_auto" or "crl_offline".
cert_policy = ca,signature,ocsp_on, crl_auto;
If the system is missing an "/etc/pam_pkcs11/" directory and an "/etc/pam_pkcs11/pam_pkcs11.conf", find an example to copy into place and modify accordingly at "/usr/share/doc/libpam-pkcs11/examples/pam_pkcs11.conf.example.gz".