Apache - directory browsing gives 404

Apache - directory browsing gives 404

With no .htaccess files and Options FollowSymLinks MultiViews Indexes followed by AllowOverride None in the vhost configuration, I'm getting 404 responses from directory listings. Are there some specific modules I need for directory listings?
My active modules are:
authz_host
deflate
dir
env
expires
headers
mime
mod-security
negotiation
php5
reqtimeout
rewrite
setenvif
ssl
unique_id
VHost Configuration:
<VirtualHost *:443>
    # SSL
    SSLEngine               On
    SSLCertificateKeyFile   /dir/ssl/ssl.key
    SSLCertificateFile      /dir/ssl/ssl.crt
    SSLSessionCacheTimeout  300
</VirtualHost>

<VirtualHost *:80 *:443>
    ServerAdmin     webmaster@localhost
    ServerAlias     domain.tld *.domain.tld
    ServerName      cl.domain.tld

    # Just a few connection resets so that I don't waste my bandwidth on "hackers"
    SecRuleEngine On
    SecRule &REQUEST_HEADERS:User-Agent     "@eq 0"         drop,phase:1
    SecRule REQUEST_HEADERS:User-Agent      "^$"            drop,phase:1

    SecRule REQUEST_LINE                    "://"           drop,phase:1

    SecRule REQUEST_URI                     "^/admin"       drop,phase:1
    SecRule REQUEST_URI                     "^/mail"        drop,phase:1
    SecRule REQUEST_URI                     "^/webmail"     drop,phase:1
    SecRule REQUEST_URI                     \\\\            drop,phase:1

    SecRule REQUEST_METHOD                  !^GET$          chain,drop,phase:1
    SecRule REQUEST_METHOD                  !^HEAD$         chain
    SecRule REQUEST_METHOD                  !^POST$
    <Directory /dir/public_html/>
            Options FollowSymLinks MultiViews Indexes
            Order allow,deny
            allow from all
    </Directory>

    DocumentRoot    /dir/public_html
</VirtualHost>