SCAP & Remediation: Lessons Learned and Path Ahead
A presentation at MITRE Developer Day in in McLean, VA, USA by Shawn Wells
SCAP & Remediation: Lessons Learned and Path Ahead SHAWN WELLS DIRECTOR, INNOVATION PROGRAMS unclass: shawn@redhat.com (+1) 443-534-0130 1
RHEL5 STIG Delay: 1,988 days
RHEL5 STIG Delay: 1,988 days RHEL6 STIG Delay: 932 days
SCAP Security Guide
In a Nutshell, SCAP Security Guide: … has had 1,943 commits from 24 contributors, representing 164,355 lines of source
In a Nutshell, SCAP Security Guide: … has had 1,943 commits from 24 contributors, representing 164,355 lines of source … took an estimated 43 years of effort (COCOMO model)
In a Nutshell, SCAP Security Guide: … has had 1,943 commits from 24 contributors, representing 164,355 lines of source … took an estimated 43 years of effort (COCOMO model) … has become upstream for DISA RHEL6 STIG, NIST NVD for JBoss EAP, NSA SNAC guide in progress
60 MINUTES, 3 GOALS [ 1 ] Review SCAP remediation initiatives @ Red Hat [ 2 ] Demonstrate current capabilities (walk the code) [ 3 ] Fedora 20 / RHEL7 Roadmap
Linking XCCDF + OVAL + Remediation
Step 1 / 3: XCCDF Short Hand <Rule id=“ ” severity=“ ”> <title> </title> <description> </description> <ocil> </ocil> <rationale> </rationale> <ident cce=“ ” /> <ref nist=“ ” disa=“ ” /> <oval id=“ ” /> </Rule>
Step 1 / 3: XCCDF Short Hand <Rule id=“ ” severity=“ ”> <title> </title> <description> </description> <ocil> </ocil> <rationale> </rationale> <ident cce=“ ” /> <ref nist=“ ” disa=“ ” /> <oval id=“ ” /> </Rule>
Step 2 / 3: OVAL Linking OVAL developed independently from XCCDF, <oval id=“”> tag matches OVAL filename: $ ls RHEL6/input/checks/ ; ls RHEL6/input/checks/ | echo “Total Checks: wc -l” accounts_dangerous_path_for_root.xml package_dovecot_removed.xml accounts_disable_post_pw_expiration.xml package_hal_removed.xml accounts_max_concurrent_login_sessions.xml package_httpd_removed.xml accounts_maximum_age_login_defs.xml package_iptables_installed.xml accounts_minimum_age_login_defs.xml package_iptables-ipv6_installed.xml accounts_no_uid_except_zero.xml package_iputils_removed.xml accounts_pam_no_nullok.xml package_irqbalance_installed.xml accounts_password_all_shadowed.xml package_kexec-tools_removed.xml accounts_password_minclass_login_defs.xml package_libcgroup_removed.xml accounts_password_minlen_login_defs.xml package_mdadm_removed.xml Total Checks: 342
Step 3 / 3: Remediation Linking • Bash first <fix system=”urn:xccdf:fix:script:sh”> yum -y install screen </fix>
Step 3 / 3: Remediation Linking • Bash first • Someday Puppet <fix-group id=”puppet-clip” system=”urn:xccdf:fix:script:puppet” xmlns=”http://checklists.nist.gov/xccdf/1.1”> <fix rule=”disable_vsftp”>class vsftp</fix> <fix rule=”package_aide_installed”>class aide</fix> </fix-group>
Step 3 / 3: Remediation Linking • Bash first • Someday Puppet • URN’s via NIST IR 7275 Rev 4, Table 17
<Rule id=”package_screen_installed” selected=”false” severity=”low”> <title xml:lang=”en-US”>Install the screen Package</title> <description xmlns:xhtml=”http://www.w3.org/1999/xhtml” xml:lang=”en-US”> ….. </description> <reference href=”http://iase.disa.mil/cci/index.html”>58</reference> <reference xmlns:dc=”http://purl.org/dc/elements/1.1/” href=”test_attestation”> </reference> <rationale xmlns:xhtml=”http://www.w3.org/1999/xhtml” xml:lang=”en-US”> ….. </rationale> <ident system=”http://cce.mitre.org”>CCE-26940-7</ident> <fix system=”urn:xccdf:fix:script:sh”> yum -y install screen </fix> <check system=”http://oval.mitre.org/XMLSchema/oval-definitions-5”> <check-content-ref name=”oval:ssg:def:897” href=”ssg-rhel6-oval.xml”/> </check> <check system=”ocil-transitional”> <check-export export-name=”the package is not installed” value-id=”conditional_clause”/> <check-content xmlns:xhtml=”http://www.w3.org/1999/xhtml”> ….. </check-content> </check> </Rule>
Inclusion of XCCDF Variables • Approached authored by Jeff Blank (NSA) • “Sourcing” XCCDF variable in bash script, build process converts to proper XCCDF • Sample source: (input/fixes/bash/set_system_login_banner.sh) source ./templates/support.sh populate login_banner_text cat <<EOF >/etc/issue $login_banner_text EOF”
Inclusion of XCCDF Variables • Final XCCDF: <Value id=”login_banner_text” operator=”equals” type=”string”> “<title xml:lang=”en-US”>Login Banner Verbiage</title> “<description xmlns:xhtml= “”http://www.w3.org/1999/xhtml” xml:lang=”en-US”> ” “…………… “</description> “<value selector=”dod_short”> ” “I’ve read & consent to terms in IS user agreem’t. “</value> </Value> “” …… <fix system=”urn:xccdf:fix:script:sh”>login_banner_text=”<sub idref=”login_banner_text”/>” cat <<EOF >/etc/issue $login_banner_text EOF </fix>”
Inclusion of XCCDF Variables • Remediation Script: cat <<EOF >/etc/issue I’ve read and consent to the terms in IS user agreem’t EOF “
Approach Limitations • fixType data type for xccdf:fix elements[1] not automated (or even included) • complexity • disruption, • reboot • …… • “undo” specification? [1] http://scap.nist.gov/specifications/xccdf/xccdf_element_dictionary.html#fixType
Online & Offline Remediation ( reference Šimon Lukašík’s blog for a great write-up: http://isimluk.livejournal.com/3573.html )
Online Remediation $ oscap xccdf eval —remediate \ —results ~/my-results-xccdf.xml \ ~/my-policy-xccdf.xml” 1. OpenSCAP will perform “first pass” evaluation 2. Upon failure, executes <fix> content 3. Returns “fixed” or “error” <result> 4. Command output logged
Offline Remediation $ oscap xccdf generate fix \ —result-id xccdf_org.openscap_testresult_stig-rhel6-server \ /var/www/html/results/results.xml \ > /tmp/remediation-script.sh”
<result>error</result> <rule-result idref=”xccdf_moc.elpmaxe.www_rule_1” time=”2013-03-22T19:15:11” weight=”1.000000”> ” “<result>error</result> ” ” ” “<message severity=”info”> ” “Fix execution comleted and returned: 1 “</message> ” ” ” “<message severity=”info”> ” “Loaded plugins: auto-update-debuginfo, langpacks, presto, ” “refresh-packagekit ” ” ” “You need to be root to perform this command. “</message> … . .” </rule-result>”
<result>fixed</result> <rule-result idref=”xccdf_moc.elpmaxe.www_rule_1” time=”2013-03-22T19:16:03” weight=”1.000000”> <result>fixed</result> <message severity=”info”>Fix execution comleted and returned: 0</message> <message severity=”info”> …. Remove 1 Package Installed size: 53 k Downloading Packages: Running Transaction Check Running Transaction Test Transaction Test Succeeded Running Transaction Erasing : 1:telnet-server-0.17-51.fc16.x86_64 1/1 Verifying : 1:telnet-server-0.17-51.fc16.x86_64 1/1 Removed: telnet-server.x86_64 1:0.17-51.fc16 </message>
Fedora 20 / RHEL7 Roadmap ( Vimeo demo by Vratislav Podzimek @ http://vimeo.com/66085973 )
Remediation During Provisioning
THANK YOU! 30
Invited by MITRE to speak about how Red Hat was able to integrate remediation with the emerging SCAP standard. This approach was later recognized in an official MITRE report as pushing the industry forward in regards to automated remediation capabilities.
for free. You
can too.
