/usr/share/php/Symfony/Component/Security/Acl/Model/ is in php-symfony-security 2.7.10-0ubuntu2.
This file is owned by root:root, with mode 0o755.
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/usr/share/php/Symfony/Component/Security/Acl/Model/AclCacheInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/AclInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/AclProviderInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/AuditLoggerInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/AuditableAclInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/AuditableEntryInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/DomainObjectInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/EntryInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/FieldEntryInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/MutableAclInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/MutableAclProviderInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/ObjectIdentityInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/ObjectIdentityRetrievalStrategyInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/PermissionGrantingStrategyInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/SecurityIdentityInterface.php
/usr/share/php/Symfony/Component/Security/Acl/Model/SecurityIdentityRetrievalStrategyInterface.php