Anchore Policy Checks

Introduction

In this document, we describe the current anchore gates (and related triggers/parameters) that are supported within anchore policy bundles. If you have a running anchore enterprise, this information can also be obtained using the CLI:

# anchore-cli policy describe (--gate <gatename> ( --trigger <triggername))

Gate: dockerfile

Checks against the content of a dockerfile if provided, or a guessed dockerfile based on docker layer history if the dockerfile is not provided.

Trigger Name Description Parameter Description Example
instruction Triggers if any directives in the list are found to match the described condition in the dockerfile. instruction The Dockerfile instruction to check. from
instruction Triggers if any directives in the list are found to match the described condition in the dockerfile. check The type of check to perform. =
instruction Triggers if any directives in the list are found to match the described condition in the dockerfile. value The value to check the dockerfile instruction against. scratch
instruction Triggers if any directives in the list are found to match the described condition in the dockerfile. actual_dockerfile_only Only evaluate against a user-provided dockerfile, skip evaluation on inferred/guessed dockerfiles. Default is False. true
effective_user Checks if the effective user matches the provided user names, either as a allowlist or blocklist depending on the type parameter setting. users User names to check against as the effective user (last user entry) in the images history. root,docker
effective_user Checks if the effective user matches the provided user names, either as a allowlist or blocklist depending on the type parameter setting. type How to treat the provided user names. blocklist
exposed_ports Evaluates the set of ports exposed. Allows configuring allowlist or blocklist behavior. If type=whitelist, then any ports found exposed that are not in the list will cause the trigger to fire. If type=blacklist, then any ports exposed that are in the list will cause the trigger to fire. ports List of port numbers. 80,8080,8088
exposed_ports Evaluates the set of ports exposed. Allows configuring allowlist or blocklist behavior. If type=whitelist, then any ports found exposed that are not in the list will cause the trigger to fire. If type=blacklist, then any ports exposed that are in the list will cause the trigger to fire. type Whether to use port list as a allowlist or blocklist. blacklist
exposed_ports Evaluates the set of ports exposed. Allows configuring allowlist or blocklist behavior. If type=whitelist, then any ports found exposed that are not in the list will cause the trigger to fire. If type=blacklist, then any ports exposed that are in the list will cause the trigger to fire. actual_dockerfile_only Only evaluate against a user-provided dockerfile, skip evaluation on inferred/guessed dockerfiles. Default is False. true
no_dockerfile_provided Triggers if anchore analysis was performed without supplying the actual image Dockerfile.

Gate: files

Checks against files in the analyzed image including file content, file names, and filesystem attributes.

Trigger Name Description Parameter Description Example
content_regex_match Triggers for each file where the content search analyzer has found a match using configured regexes in the analyzer_config.yaml “content_search” section. If the parameter is set, the trigger will only fire for files that matched the named regex. Refer to your analyzer_config.yaml for the regex values. regex_name Regex string that also appears in the FILECHECK_CONTENTMATCH analyzer parameter in analyzer configuration, to limit the check to. If set, will only fire trigger when the specific named regex was found in a file. .password.
name_match Triggers if a file exists in the container that has a filename that matches the provided regex. This does have a performance impact on policy evaluation. regex Regex to apply to file names for match. .*.pem
attribute_match Triggers if a filename exists in the container that has attributes that match those which are provided . This check has a performance impact on policy evaluation. filename Filename to check against provided checksum. /etc/passwd
attribute_match Triggers if a filename exists in the container that has attributes that match those which are provided . This check has a performance impact on policy evaluation. checksum_algorithm Checksum algorithm sha256
attribute_match Triggers if a filename exists in the container that has attributes that match those which are provided . This check has a performance impact on policy evaluation. checksum Checksum of file. 832cd0f75b227d13aac82b1f70b7f90191a4186c151f9db50851d209c45ede11
attribute_match Triggers if a filename exists in the container that has attributes that match those which are provided . This check has a performance impact on policy evaluation. checksum_match Checksum operation to perform. equals
attribute_match Triggers if a filename exists in the container that has attributes that match those which are provided . This check has a performance impact on policy evaluation. mode File mode of file. 00644
attribute_match Triggers if a filename exists in the container that has attributes that match those which are provided . This check has a performance impact on policy evaluation. mode_op File mode operation to perform. equals
attribute_match Triggers if a filename exists in the container that has attributes that match those which are provided . This check has a performance impact on policy evaluation. skip_missing If set to true, do not fire this trigger if the file is not present. If set to false, fire this trigger ignoring the other parameter settings. true
suid_or_guid_set Fires for each file found to have suid or sgid bit set.

Gate: passwd_file

Content checks for /etc/passwd for things like usernames, group ids, shells, or full entries.

Trigger Name Description Parameter Description Example
content_not_available Triggers if the /etc/passwd file is not present/stored in the evaluated image.
blacklist_usernames Triggers if specified username is found in the /etc/passwd file user_names List of usernames that will cause the trigger to fire if found in /etc/passwd. daemon,ftp
blacklist_userids Triggers if specified user id is found in the /etc/passwd file user_ids List of userids (numeric) that will cause the trigger to fire if found in /etc/passwd. 0,1
blacklist_groupids Triggers if specified group id is found in the /etc/passwd file group_ids List of groupids (numeric) that will cause the trigger ot fire if found in /etc/passwd. 999,20
blacklist_shells Triggers if specified login shell for any user is found in the /etc/passwd file shells List of shell commands to blacklist. /bin/bash,/bin/zsh
blacklist_full_entry Triggers if entire specified passwd entry is found in the /etc/passwd file. entry Full entry to match in /etc/passwd. ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin

Gate: packages

Distro package checks

Trigger Name Description Parameter Description Example
required_package Triggers if the specified package and optionally a specific version is not found in the image. name Name of package that must be found installed in image. libssl
required_package Triggers if the specified package and optionally a specific version is not found in the image. version Optional version of package for exact version match. 1.10.3rc3
required_package Triggers if the specified package and optionally a specific version is not found in the image. version_match_type The type of comparison to use for version if a version is provided. exact
verify Check package integrity against package db in the image. Triggers for changes or removal or content in all or the selected “dirs” parameter if provided, and can filter type of check with the “check_only” parameter. only_packages List of package names to limit verification. libssl,openssl
verify Check package integrity against package db in the image. Triggers for changes or removal or content in all or the selected “dirs” parameter if provided, and can filter type of check with the “check_only” parameter. only_directories List of directories to limit checks so as to avoid checks on all dir. /usr,/var/lib
verify Check package integrity against package db in the image. Triggers for changes or removal or content in all or the selected “dirs” parameter if provided, and can filter type of check with the “check_only” parameter. check Check to perform instead of all. changed
blacklist Triggers if the evaluated image has a package installed that matches the named package optionally with a specific version as well. name Package name to blacklist. openssh-server
blacklist Triggers if the evaluated image has a package installed that matches the named package optionally with a specific version as well. version Specific version of package to blacklist. 1.0.1

Gate: vulnerabilities

CVE/Vulnerability checks.

Trigger Name Description Parameter Description Example
package Triggers if a found vulnerability in an image meets the comparison criteria. package_type Only trigger for specific package type. all
package Triggers if a found vulnerability in an image meets the comparison criteria. severity_comparison The type of comparison to perform for severity evaluation. >
package Triggers if a found vulnerability in an image meets the comparison criteria. severity Severity to compare against. high
package Triggers if a found vulnerability in an image meets the comparison criteria. cvss_v3_base_score_comparison The type of comparison to perform for CVSS v3 base score evaluation. >
package Triggers if a found vulnerability in an image meets the comparison criteria. cvss_v3_base_score CVSS v3 base score to compare against. None
package Triggers if a found vulnerability in an image meets the comparison criteria. cvss_v3_exploitability_score_comparison The type of comparison to perform for CVSS v3 exploitability sub score evaluation. >
package Triggers if a found vulnerability in an image meets the comparison criteria. cvss_v3_exploitability_score CVSS v3 exploitability sub score to compare against. None
package Triggers if a found vulnerability in an image meets the comparison criteria. cvss_v3_impact_score_comparison The type of comparison to perform for CVSS v3 impact sub score evaluation. >
package Triggers if a found vulnerability in an image meets the comparison criteria. cvss_v3_impact_score CVSS v3 impact sub score to compare against. None
package Triggers if a found vulnerability in an image meets the comparison criteria. fix_available If present, the fix availability for the vulnerability record must match the value of this parameter. true
package Triggers if a found vulnerability in an image meets the comparison criteria. vendor_only If True, an available fix for this CVE must not be explicitly marked as wont be addressed by the vendor true
package Triggers if a found vulnerability in an image meets the comparison criteria. max_days_since_creation If provided, this CVE must be older than the days provided to trigger. 7
package Triggers if a found vulnerability in an image meets the comparison criteria. max_days_since_fix If provided (only evaluated when fix_available option is also set to true), the fix first observed time must be older than days provided, to trigger. 30
package Triggers if a found vulnerability in an image meets the comparison criteria. vendor_cvss_v3_base_score_comparison The type of comparison to perform for vendor specified CVSS v3 base score evaluation. >
package Triggers if a found vulnerability in an image meets the comparison criteria. vendor_cvss_v3_base_score Vendor CVSS v3 base score to compare against. None
package Triggers if a found vulnerability in an image meets the comparison criteria. vendor_cvss_v3_exploitability_score_comparison The type of comparison to perform for vendor specified CVSS v3 exploitability sub score evaluation. >
package Triggers if a found vulnerability in an image meets the comparison criteria. vendor_cvss_v3_exploitability_score Vendor CVSS v3 exploitability sub score to compare against. None
package Triggers if a found vulnerability in an image meets the comparison criteria. vendor_cvss_v3_impact_score_comparison The type of comparison to perform for vendor specified CVSS v3 impact sub score evaluation. >
package Triggers if a found vulnerability in an image meets the comparison criteria. vendor_cvss_v3_impact_score Vendor CVSS v3 impact sub score to compare against. None
blacklist Triggers if any of a list of specified vulnerabilities has been detected in the image. vulnerability_ids List of vulnerability IDs, will cause the trigger to fire if any are detected. CVE-2019-1234
blacklist Triggers if any of a list of specified vulnerabilities has been detected in the image. vulnerability_ids If set to True, discard matches against this vulnerability if vendor has marked as will not fix in the vulnerability record. True
stale_feed_data Triggers if the CVE data is older than the window specified by the parameter MAXAGE (unit is number of days). max_days_since_sync Fire the trigger if the last sync was more than this number of days ago. 10
vulnerability_data_unavailable Triggers if vulnerability data is unavailable for the image’s distro.

Gate: licenses

License checks against found software licenses in the container image

Trigger Name Description Parameter Description Example
blacklist_exact_match Triggers if the evaluated image has a package installed with software distributed under the specified (exact match) license(s). licenses List of license names to blacklist exactly. GPLv2+,GPL-3+,BSD-2-clause
blacklist_partial_match triggers if the evaluated image has a package installed with software distributed under the specified (substring match) license(s) licenses List of strings to do substring match for blacklist. LGPL,BSD

Gate: ruby_gems

Ruby Gem Checks

Trigger Name Description Parameter Description Example
newer_version_found_in_feed Triggers if an installed GEM is not the latest version according to GEM data feed.
not_found_in_feed Triggers if an installed GEM is not in the official GEM database, according to GEM data feed.
version_not_found_in_feed Triggers if an installed GEM version is not listed in the official GEM feed as a valid version.
blacklist Triggers if the evaluated image has a GEM package installed that matches the specified name and version. name Gem name to blacklist. time_diff
blacklist Triggers if the evaluated image has a GEM package installed that matches the specified name and version. version Optional version to blacklist specifically. 0.2.9
feed_data_unavailable Triggers if anchore does not have access to the GEM data feed.

Gate: npms

NPM Checks

Trigger Name Description Parameter Description Example
newer_version_in_feed Triggers if an installed NPM is not the latest version according to NPM data feed.
unknown_in_feeds Triggers if an installed NPM is not in the official NPM database, according to NPM data feed.
version_not_in_feeds Triggers if an installed NPM version is not listed in the official NPM feed as a valid version.
blacklisted_name_version Triggers if the evaluated image has an NPM package installed that matches the name and optionally a version specified in the parameters. name Npm package name to blacklist. time_diff
blacklisted_name_version Triggers if the evaluated image has an NPM package installed that matches the name and optionally a version specified in the parameters. version Npm package version to blacklist specifically. 0.2.9
feed_data_unavailable Triggers if the system does not have access to the NPM data feed.

Gate: secret_scans

Checks for secrets and content found in the image using configured regexes found in the “secret_search” section of analyzer_config.yaml.

Trigger Name Description Parameter Description Example
content_regex_checks Triggers if the secret content search analyzer has found any matches with the configured and named regexes. Checks can be configured to trigger if a match is found or is not found (selected using match_type parameter). Matches are filtered by the content_regex_name and filename_regex if they are set. The content_regex_name shoud be a value from the “secret_search” section of the analyzer_config.yaml. content_regex_name Name of content regexps configured in the analyzer that match if found in the image, instead of matching all. Names available by default are: [‘AWS_ACCESS_KEY’, ‘AWS_SECRET_KEY’, ‘PRIV_KEY’, ‘DOCKER_AUTH’, ‘API_KEY’]. AWS_ACCESS_KEY
content_regex_checks Triggers if the secret content search analyzer has found any matches with the configured and named regexes. Checks can be configured to trigger if a match is found or is not found (selected using match_type parameter). Matches are filtered by the content_regex_name and filename_regex if they are set. The content_regex_name shoud be a value from the “secret_search” section of the analyzer_config.yaml. filename_regex Regexp to filter the content matched files by. /etc/.*
content_regex_checks Triggers if the secret content search analyzer has found any matches with the configured and named regexes. Checks can be configured to trigger if a match is found or is not found (selected using match_type parameter). Matches are filtered by the content_regex_name and filename_regex if they are set. The content_regex_name shoud be a value from the “secret_search” section of the analyzer_config.yaml. match_type Set to define the type of match - trigger if match is found (default) or not found. found

Gate: metadata

Checks against image metadata, such as size, OS, distro, architecture, etc.

Trigger Name Description Parameter Description Example
attribute Triggers if a named image metadata value matches the given condition. attribute Attribute name to be checked. size
attribute Triggers if a named image metadata value matches the given condition. check The operation to perform the evaluation. >
attribute Triggers if a named image metadata value matches the given condition. value Value used in comparison. 1073741824

Gate: always

Triggers that fire unconditionally if present in policy, useful for things like testing and blacklisting.

Trigger Name Description Parameter Description Example
always Fires if present in a policy being evaluated. Useful for things like blacklisting images or testing mappings and allowlists by using this trigger in combination with policy mapping rules.

Gate: retrieved_files

Checks against content and/or presence of files retrieved at analysis time from an image

Trigger Name Description Parameter Description Example
content_not_available Triggers if the specified file is not present/stored in the evaluated image. path The path of the file to verify has been retrieved during analysis /etc/httpd.conf
content_regex Evaluation of regex on retrieved file content path The path of the file to verify has been retrieved during analysis /etc/httpd.conf
content_regex Evaluation of regex on retrieved file content check The type of check to perform with the regex match
content_regex Evaluation of regex on retrieved file content regex The regex to evaluate against the content of the file .SSlEnabled.

Gate: Malware

Trigger Description Parameters
scans Triggers if any malware scanner has found any matches in the image.
scan_not_run Triggers if no scan was found for the image.

Next Steps

Now that you have a good grasp on the core concepts and architecture, check out the Requirements section for running Anchore.


Last modified February 4, 2021: Changes whitelist to allowlist and blacklist to blocklist where possible (e821452)