htaccess правила для предотвращения исполнения вредоносных PHP-скриптов.

<Files .htaccess>
Order allow,deny
Deny from all
</Files>

<FilesMatch "\.(php)$">
Order allow,deny
Deny from all
</FilesMatch>

<Directory /path/to/directory>
<FilesMatch "\.(php)$">
Order allow,deny
Deny from all
</FilesMatch>
</Directory>

RemoveHandler .php .phtml .php3
RemoveType .php .phtml .php3

<Directory /path/to/directory>
<FilesMatch "\.php$">
Order allow,deny
Deny from all
</FilesMatch>
</Directory>

# Блокировка XSS
RewriteCond %{QUERY_STRING} (\<|%3C).*script.*(\>|%3E) [NC,OR]
# Блокируем выставление переменной PHP GLOBALS через URL
RewriteCond %{QUERY_STRING} GLOBALS(=|\[|\%[0-9A-Z]{0,2}) [OR]
# Блокируем возможность изменять переменную _REQUEST через URL
RewriteCond %{QUERY_STRING} _REQUEST(=|\[|\%[0-9A-Z]{0,2})

# Блокировка MySQL инъекций, RFI, base64, и др.
RewriteCond %{QUERY_STRING} [a-zA-Z0-9_]=http:// [OR]
RewriteCond %{QUERY_STRING} [a-zA-Z0-9_]=(\.\.//?)+ [OR]
RewriteCond %{QUERY_STRING} [a-zA-Z0-9_]=/([a-z0-9_.]//?)+ [NC,OR]
RewriteCond %{QUERY_STRING} \=PHP[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12} [NC,OR]
RewriteCond %{QUERY_STRING} (\.\./|\.\.) [OR]
RewriteCond %{QUERY_STRING} ftp\: [NC,OR]
RewriteCond %{QUERY_STRING} http\: [NC,OR]
RewriteCond %{QUERY_STRING} https\: [NC,OR]
RewriteCond %{QUERY_STRING} \=\|w\| [NC,OR]
RewriteCond %{QUERY_STRING} ^(.*)/self/(.*)$ [NC,OR]
RewriteCond %{QUERY_STRING} ^(.*)cPath=http://(.*)$ [NC,OR]
RewriteCond %{QUERY_STRING} (\<|%3C).*script.*(\>|%3E) [NC,OR]
RewriteCond %{QUERY_STRING} (<|%3C)([^s]*s)+cript.*(>|%3E) [NC,OR]
RewriteCond %{QUERY_STRING} (\<|%3C).*iframe.*(\>|%3E) [NC,OR]
RewriteCond %{QUERY_STRING} (<|%3C)([^i]*i)+frame.*(>|%3E) [NC,OR]
RewriteCond %{QUERY_STRING} mosConfig_[a-zA-Z_]{1,21}(=|%3D) [OR]
RewriteCond %{QUERY_STRING} base64_encode.*\(.*\) [NC,OR]
RewriteCond %{QUERY_STRING} base64_(en|de)code[^(]*\([^)]*\) [NC,OR]
RewriteCond %{QUERY_STRING} ^.*(\[|\]|\(|\)|<|>).* [NC,OR]
RewriteCond %{QUERY_STRING} (NULL|OUTFILE|LOAD_FILE) [OR]
RewriteCond %{QUERY_STRING} (\./|\../|\.../)+(motd|etc|bin) [NC,OR]
RewriteCond %{QUERY_STRING} (localhost|loopback|127\.0\.0\.1) [NC,OR]
RewriteCond %{QUERY_STRING} (<|>|'|%0A|%0D|%27|%3C|%3E|%00) [NC,OR]
RewriteCond %{QUERY_STRING} concat[^\(]*\( [NC,OR]
RewriteCond %{QUERY_STRING} union([^s]*s)+elect [NC,OR]
RewriteCond %{QUERY_STRING} union([^a]*a)+ll([^s]*s)+elect [NC,OR]
RewriteCond %{QUERY_STRING} (;|<|>|'|"|\)|%0A|%0D|%22|%27|%3C|%3E|%00).*(/\*|union|select|insert|drop|delete|update|cast|create|char|convert|alter|declare|order|script|set|md5|benchmark|encode) [NC,OR]
RewriteCond %{QUERY_STRING} (\\|\.\.\.|\.\./|~|`|<|>|\|) [NC,OR]
RewriteCond %{QUERY_STRING} (boot\.ini|etc/passwd|self/environ) [NC,OR]
RewriteCond %{QUERY_STRING} (thumbs?(_editor|open)?|tim(thumb)?)\.php [NC,OR]
RewriteCond %{QUERY_STRING} (sp_executesql) [NC]
RewriteCond %{QUERY_STRING} (eval\() [NC,OR]
RewriteCond %{QUERY_STRING} (127\.0\.0\.1) [NC,OR]
RewriteCond %{QUERY_STRING} ([a-z0-9]{2000,}) [NC,OR]
RewriteRule ^(.*)$ - [F,L]

# Отклонение запросов TRACE|TRACK
RewriteCond %{REQUEST_METHOD} ^(TRACE|TRACK)  
RewriteRule .* - [F]

# Фильтрация URL на служебные символы
RewriteCond %{QUERY_STRING} (<|>|'|\+|%2B|%0A|%0D|%27|%3C|%3E|%00) [NC,OR]

# Блокировка известных Shell
RewriteEngine on
RewriteCond %{REQUEST_URI} .*((php|my)?shell|remview.*|phpremoteview.*|sshphp.*|pcom|nstview.*|c99|r57|webadmin.*|phpget.*|phpwriter.*|fileditor.*|locus7.*|storm7.*).(p?s?x?htm?l?|txt|aspx?|cfml?|cgi|pl|php[3-9]{0,1}|jsp?|sql|xml) [NC,OR]
RewriteCond %{REQUEST_METHOD} (GET|POST) [NC]
RewriteCond %{QUERY_STRING} ^(.*)=(/|%2F)(h|%68|%48)(o|%6F|%4F)(m|%6D|%4D)(e|%65|%45)(.+)?(/|%2F)(.*)(/|%2F)(.*)$ [OR]
RewriteCond %{QUERY_STRING} ^work_dir=.*$ [OR]
RewriteCond %{QUERY_STRING} ^command=.*&output.*$ [OR]
RewriteCond %{QUERY_STRING} ^nts_[a-z0-9_]{0,10}=.*$ [OR]
RewriteCond %{QUERY_STRING} ^c=(t|setup|codes)$ [OR]
RewriteCond %{QUERY_STRING} ^act=((about|cmd|selfremove|chbd|trojan|backc|massbrowsersploit|exploits|grablogins|upload.*)|((chmod|f)&f=.*))$ [OR]
RewriteCond %{QUERY_STRING} ^act=(ls|search|fsbuff|encoder|tools|processes|ftpquickbrute|security|sql|eval|update|feedback|cmd|gofile|mkfile)&d=.*$ [OR]
RewriteCond %{QUERY_STRING} ^&?c=(l?v?i?&d=|v&fnot=|setup&ref=|l&r=|d&d=|tree&d|t&d=|e&d=|i&d=|codes|md5crack).*$ [OR]
RewriteCond %{QUERY_STRING} ^(.*)([-_a-z]{1,15})=(chmod|chdir|mkdir|rmdir|clear|whoami|uname|unzip|gzip|gunzip|grep|more|umask|telnet|ssh|ftp|head|tail|which|mkmode|touch|logname|edit_file|search_text|find_text|php_eval|download_file|ftp_file_down|ftp_file_up|ftp_brute|mail_file|mysql|mysql_dump|db_query)([^a-zA-Z0-9].+)*$ [OR]
# Удалите из слудующей строки слово "system" для нормальной работы информационных систем HostCMS
RewriteCond %{QUERY_STRING} ^(.*)(wget|shell_exec|passthru|system|exec|popen|proc_open)(.*)$
RewriteRule .* - [F]

# Отклонение плохо сформированных запросов HTTP
RewriteEngine on
RewriteCond %{THE_REQUEST} !^[A-Z]{3,9} .+ HTTP/(0.9|1.0|1.1) [NC]
RewriteRule .* - [F,NS,L]

# Запрет любых запросов кроме GET,PROPFIND,POST,OPTIONS,PUT,HEAD
RewriteEngine on
RewriteCond %{REQUEST_METHOD} !^(GET|HEAD|POST|PROPFIND|OPTIONS|PUT)$ [NC]
RewriteRule .* - [F,NS,L]

# Блокировка от LFi-атак (экспериментальное, см. комментарии)
RewriteCond %{REQUEST_METHOD} GET
RewriteCond %{QUERY_STRING} [a-zA-Z0-9_]=http:// [OR]
RewriteCond %{QUERY_STRING} [a-zA-Z0-9_]=http%3A%2F%2F [OR]
RewriteCond %{QUERY_STRING} [a-zA-Z0-9_]=(..//?)+ [OR]
RewriteCond %{QUERY_STRING} [a-zA-Z0-9_]=/([a-z0-9_.]//?)+ [NC]
RewriteRule .* - [F]