1 files changed, 374 insertions, 0 deletions

diff --git a/data/php.yar b/data/php.yar
new file mode 100644
index 0000000..4470e1b
--- /dev/null
+++ b/data/php.yar
@@ -0,0 +1,374 @@
+import "hash"
+include "whitelist.yar"
+
+/*
+    Detect:
+        - phpencode.org
+        - http://www.pipsomania.com/best_php_obfuscator.do
+        - http://atomiku.com/online-php-code-obfuscator/
+        - http://www.webtoolsvn.com/en-decode/
+        - http://obfuscator.uk/example/
+        - http://w3webtools.com/encode-php-online/
+        - http://www.joeswebtools.com/security/php-obfuscator/
+        - https://github.com/epinna/weevely3
+        - http://cipherdesign.co.uk/service/php-obfuscator
+        - http://sysadmin.cyklodev.com/online-php-obfuscator/
+        - http://mohssen.org/SpinObf.php
+        - https://code.google.com/p/carbylamine/
+        - https://github.com/tennc/webshell
+
+        - https://github.com/wireghoul/htshells
+
+    Thanks to:
+        - https://stackoverflow.com/questions/3115559/exploitable-php-functions
+*/
+
+global private rule IsPhp
+{
+    strings:
+        $php = /<\?[^x]/
+
+    condition:
+        $php and filesize < 5MB
+}
+
+rule NonPrintableChars
+{
+  strings:
+    /*
+    Searching only for non-printable characters completely kills the perf,
+    so we have to use atoms (https://gist.github.com/Neo23x0/e3d4e316d7441d9143c7)
+    to get an acceptable speed.
+    */
+    $non_printables = /(function|return|base64_decode).{,256}[^\x09-\x0d\x20-\x7E]{3}/
+
+  condition:
+        (any of them) and not IsWhitelisted
+}
+
+
+rule PasswordProtection
+{
+    strings:
+        $md5 = /md5\s*\(\s*\$_(GET|REQUEST|POST|COOKIE|SERVER)[^)]+\)\s*===?\s*['"][0-9a-f]{32}['"]/ nocase
+        $sha1 = /sha1\s*\(\s*\$_(GET|REQUEST|POST|COOKIE|SERVER)[^)]+\)\s*===?\s*['"][0-9a-f]{40}['"]/ nocase
+    condition:
+        (any of them) and not IsWhitelisted
+}
+
+rule ObfuscatedPhp
+{
+    strings:
+        $eval = /(<\?php|[;{}])[ \t]*@?(eval|preg_replace|system|assert|passthru|(pcntl_)?exec|shell_exec|call_user_func(_array)?)\s*\(/ nocase  // ;eval( <- this is dodgy
+        $eval_comment = /(eval|preg_replace|system|assert|passthru|(pcntl_)?exec|shell_exec|call_user_func(_array)?)\/\*[^\*]*\*\/\(/ nocase  // eval/*lol*/( <- this is dodgy
+        $b374k = "'ev'.'al'"
+        $align = /(\$\w+=[^;]*)*;\$\w+=@?\$\w+\(/  //b374k
+        $weevely3 = /\$\w=\$[a-zA-Z]\('',\$\w\);\$\w\(\);/  // weevely3 launcher
+        $c99_launcher = /;\$\w+\(\$\w+(,\s?\$\w+)+\);/  // http://bartblaze.blogspot.fr/2015/03/c99shell-not-dead.html
+        $nano = /\$[a-z0-9-_]+\[[^]]+\]\(/ //https://github.com/UltimateHackers/nano
+        $ninja = /base64_decode[^;]+getallheaders/ //https://github.com/UltimateHackers/nano
+        $variable_variable = /\${\$[0-9a-zA-z]+}/
+        $too_many_chr = /(chr\([\d]+\)\.){8}/  // concatenation of more than eight `chr()`
+        $concat = /(\$[^\n\r]+\.){5}/  // concatenation of more than 5 words
+        $concat_with_spaces = /(\$[^\n\r]+\. ){5}/  // concatenation of more than 5 words, with spaces
+        $var_as_func = /\$_(GET|POST|COOKIE|REQUEST|SERVER)\s*\[[^\]]+\]\s*\(/
+        $comment = /\/\*([^*]|\*[^\/])*\*\/\s*\(/  // eval /* comment */ (php_code)
+condition:
+        (any of them) and not IsWhitelisted
+}
+
+rule DodgyPhp
+{
+    strings:
+        $basedir_bypass = /curl_init\s*\(\s*["']file:\/\// nocase
+        $basedir_bypass2 = "file:file:///" // https://www.intelligentexploit.com/view-details.html?id=8719
+        $disable_magic_quotes = /set_magic_quotes_runtime\s*\(\s*0/ nocase
+
+        $execution = /\b(popen|eval|assert|passthru|exec|include|system|pcntl_exec|shell_exec|base64_decode|`|array_map|ob_start|call_user_func(_array)?)\s*\(\s*(base64_decode|php:\/\/input|str_rot13|gz(inflate|uncompress)|getenv|pack|\\?\$_(GET|REQUEST|POST|COOKIE|SERVER))/ nocase  // function that takes a callback as 1st parameter
+        $execution2 = /\b(array_filter|array_reduce|array_walk(_recursive)?|array_walk|assert_options|uasort|uksort|usort|preg_replace_callback|iterator_apply)\s*\(\s*[^,]+,\s*(base64_decode|php:\/\/input|str_rot13|gz(inflate|uncompress)|getenv|pack|\\?\$_(GET|REQUEST|POST|COOKIE|SERVER))/ nocase  // functions that takes a callback as 2nd parameter
+        $execution3 = /\b(array_(diff|intersect)_u(key|assoc)|array_udiff)\s*\(\s*([^,]+\s*,?)+\s*(base64_decode|php:\/\/input|str_rot13|gz(inflate|uncompress)|getenv|pack|\\?\$_(GET|REQUEST|POST|COOKIE|SERVER))\s*\[[^]]+\]\s*\)+\s*;/ nocase  // functions that takes a callback as 2nd parameter
+
+        $htaccess = "SetHandler application/x-httpd-php"
+        $iis_com = /IIS:\/\/localhost\/w3svc/
+        $include = /include\s*\(\s*[^\.]+\.(png|jpg|gif|bmp)/  // Clever includes
+        $ini_get = /ini_(get|set|restore)\s*\(\s*['"](safe_mode|open_basedir|disable_(function|classe)s|safe_mode_exec_dir|safe_mode_include_dir|register_globals|allow_url_include)/ nocase
+        $pr = /(preg_replace(_callback)?|mb_ereg_replace|preg_filter)\s*\([^)]*(\/|\\x2f)(e|\\x65)['"]/  nocase // http://php.net/manual/en/function.preg-replace.php
+        $register_function = /register_[a-z]+_function\s*\(\s*['"]\s*(eval|assert|passthru|exec|include|system|shell_exec|`)/  // https://github.com/nbs-system/php-malware-finder/issues/41
+        $safemode_bypass = /\x00\/\.\.\/|LD_PRELOAD/
+        $shellshock = /\(\)\s*{\s*[a-z:]\s*;\s*}\s*;/
+        $udp_dos = /fsockopen\s*\(\s*['"]udp:\/\// nocase
+        $various = "<!--#exec cmd="  //http://www.w3.org/Jigsaw/Doc/User/SSI.html#exec
+        $at_eval = /@eval\s*\(/ nocase
+        $double_var = /\${\s*\${/
+        $extract = /extract\s*\(\s*\$_(GET|POST|REQUEST|COOKIE|SERVER)/
+        $reversed = /noitcnuf_etaerc|metsys|urhtssap|edulcni|etucexe_llehs/ nocase
+                                $silenced_include =/@\s*include\s*/ nocase
+
+    condition:
+        (any of them) and not IsWhitelisted
+}
+
+rule DangerousPhp
+{
+    strings:
+        $system = "system" fullword nocase  // localroot bruteforcers have a lot of this
+
+        $ = "array_filter" fullword nocase
+        $ = "assert" fullword nocase
+        $ = "backticks" fullword nocase
+        $ = "call_user_func" fullword nocase
+        $ = "eval" fullword nocase
+        $ = "exec" fullword nocase
+        $ = "fpassthru" fullword nocase
+        $ = "fsockopen" fullword nocase
+        $ = "function_exists" fullword nocase
+        $ = "getmygid" fullword nocase
+        $ = "shmop_open" fullword nocase
+        $ = "mb_ereg_replace_callback" fullword nocase
+        $ = "passthru" fullword nocase
+        $ = /pcntl_(exec|fork)/ fullword nocase
+        $ = "php_uname" fullword nocase
+        $ = "phpinfo" fullword nocase
+        $ = "posix_geteuid" fullword nocase
+        $ = "posix_getgid" fullword nocase
+        $ = "posix_getpgid" fullword nocase
+        $ = "posix_getppid" fullword nocase
+        $ = "posix_getpwnam" fullword nocase
+        $ = "posix_getpwuid" fullword nocase
+        $ = "posix_getsid" fullword nocase
+        $ = "posix_getuid" fullword nocase
+        $ = "posix_kill" fullword nocase
+        $ = "posix_setegid" fullword nocase
+        $ = "posix_seteuid" fullword nocase
+        $ = "posix_setgid" fullword nocase
+        $ = "posix_setpgid" fullword nocase
+        $ = "posix_setsid" fullword nocase
+        $ = "posix_setsid" fullword nocase
+        $ = "posix_setuid" fullword nocase
+        $ = "preg_replace_callback" fullword
+        $ = "proc_open" fullword nocase
+        $ = "proc_close" fullword nocase
+        $ = "popen" fullword nocase
+        $ = "register_shutdown_function" fullword nocase
+        $ = "register_tick_function" fullword nocase
+        $ = "shell_exec" fullword nocase
+        $ = "shm_open" fullword nocase
+        $ = "show_source" fullword nocase
+        $ = "socket_create(AF_INET, SOCK_STREAM, SOL_TCP)" nocase
+        $ = "stream_socket_pair" nocase
+        $ = "suhosin.executor.func.blacklist" nocase
+        $ = "unregister_tick_function" fullword nocase
+        $ = "win32_create_service" fullword nocase
+        $ = "xmlrpc_decode" fullword nocase 
+        $ = /ob_start\s*\(\s*[^\)]/  //ob_start('assert'); echo $_REQUEST['pass']; ob_end_flush();
+
+        $whitelist = /escapeshellcmd|escapeshellarg/ nocase
+
+    condition:
+        (not $whitelist and (5 of them or #system > 250)) and not IsWhitelisted
+}
+
+rule HiddenInAFile
+{
+    strings:
+        $gif = {47 49 46 38 ?? 61} // GIF8[version]a
+        $png = {89 50 4E 47 0D 0a 1a 0a} // \X89png\X0D\X0A\X1A\X0A
+        $jpeg = {FF D8 FF E0 ?? ?? 4A 46 49 46 } // https://raw.githubusercontent.com/corkami/pics/master/JPG.png
+
+    condition:
+        ($gif at 0 or $png at 0 or $jpeg at 0) and (PasswordProtection or ObfuscatedPhp or DodgyPhp or DangerousPhp) and not IsWhitelisted
+}
+
+rule CloudFlareBypass
+{
+    strings:
+        $ = "chk_jschl"
+        $ = "jschl_vc"
+        $ = "jschl_answer"
+
+    condition:
+        2 of them // Better be safe than sorry
+}
+
+private rule IRC
+{
+    strings:
+        $ = "USER" fullword nocase
+        $ = "PASS" fullword nocase
+        $ = "PRIVMSG" fullword nocase
+        $ = "MODE" fullword nocase
+        $ = "PING" fullword nocase
+        $ = "PONG" fullword nocase
+        $ = "JOIN" fullword nocase
+        $ = "PART" fullword nocase
+
+    condition:
+        5 of them
+}
+
+private rule b64
+{
+    strings:
+        $user_agent = "SFRUUF9VU0VSX0FHRU5UCg"
+        $eval = "ZXZhbCg"
+        $system = "c3lzdGVt"
+        $preg_replace = "cHJlZ19yZXBsYWNl"
+        $exec = "ZXhlYyg"
+        $base64_decode = "YmFzZTY0X2RlY29kZ"
+        $perl_shebang = "IyEvdXNyL2Jpbi9wZXJsCg"
+        $cmd_exe = "Y21kLmV4ZQ"
+        $powershell = "cG93ZXJzaGVsbC5leGU"
+
+    condition:
+        any of them
+}
+
+private rule hex
+{
+    strings:
+        $globals = "\\x47\\x4c\\x4f\\x42\\x41\\x4c\\x53" nocase
+        $eval = "\\x65\\x76\\x61\\x6C\\x28" nocase
+        $exec = "\\x65\\x78\\x65\\x63" nocase
+        $system = "\\x73\\x79\\x73\\x74\\x65\\x6d" nocase
+        $preg_replace = "\\x70\\x72\\x65\\x67\\x5f\\x72\\x65\\x70\\x6c\\x61\\x63\\x65" nocase
+        $http_user_agent = "\\x48\\124\\x54\\120\\x5f\\125\\x53\\105\\x52\\137\\x41\\107\\x45\\116\\x54" nocase
+        $base64_decode = "\\x61\\x73\\x65\\x36\\x34\\x5f\\x64\\x65\\x63\\x6f\\x64\\x65\\x28\\x67\\x7a\\x69\\x6e\\x66\\x6c\\x61\\x74\\x65\\x28" nocase
+    
+    condition:
+        any of them
+}
+
+private rule Hpack
+{
+    strings:
+    $globals = "474c4f42414c53" nocase
+        $eval = "6576616C28" nocase
+        $exec = "65786563" nocase
+        $system = "73797374656d" nocase
+        $preg_replace = "707265675f7265706c616365" nocase
+        $base64_decode = "61736536345f6465636f646528677a696e666c61746528" nocase
+    
+    condition:
+        any of them
+}
+
+private rule strrev
+{
+    strings:
+        $globals = "slabolg" nocase fullword
+        $preg_replace = "ecalper_gerp" nocase fullword
+        $base64_decode = "edoced_46esab" nocase fullword
+        $gzinflate = "etalfnizg" nocase fullword
+    
+    condition:
+        any of them
+}
+
+
+rule SuspiciousEncoding
+{
+    condition:
+        (b64 or hex or strrev or Hpack) and not IsWhitelisted
+}
+
+rule DodgyStrings
+{
+    strings:
+        $ = ".bash_history"
+        $ = /AddType\s+application\/x-httpd-(php|cgi)/ nocase
+        $ = /php_value\s*auto_prepend_file/ nocase
+        $ = /SecFilterEngine\s+Off/ nocase  // disable modsec
+        $ = /Add(Handler|Type|OutputFilter)\s+[^\s]+\s+\.htaccess/ nocase
+        $ = ".mysql_history"
+        $ = ".ssh/authorized_keys"
+        $ = "/(.*)/e"  // preg_replace code execution
+        $ = "/../../../"
+        $ = "/etc/passwd"
+        $ = "/etc/proftpd.conf"
+        $ = "/etc/resolv.conf"
+        $ = "/etc/shadow"
+        $ = "/etc/syslog.conf"
+        $ = "/proc/cpuinfo" fullword
+        $ = "/var/log/lastlog"
+        $ = "/windows/system32/"
+        $ = "LOAD DATA LOCAL INFILE" nocase
+        $ = "WScript.Shell"
+        $ = "WinExec"
+        $ = "b374k" fullword nocase
+        $ = "backdoor" fullword nocase
+        $ = /(c99|r57|fx29)shell/
+        $ = "cmd.exe" fullword nocase
+        $ = "powershell.exe" fullword nocase
+        $ = /defac(ed|er|ement|ing)/ fullword nocase
+        $ = "evilc0ders" fullword nocase
+        $ = "exploit" fullword nocase
+        $ = "find . -type f" fullword
+        $ = "hashcrack" nocase
+        $ = "id_rsa" fullword
+        $ = "ipconfig" fullword nocase
+        $ = "kernel32.dll" fullword nocase
+        $ = "kingdefacer" nocase
+        $ = "Wireghoul" nocase fullword
+        $ = "LD_PRELOAD" fullword
+        $ = "libpcprofile"  // CVE-2010-3856 local root
+        $ = "locus7s" nocase
+        $ = "ls -la" fullword
+        $ = "meterpreter" fullword
+        $ = "nc -l" fullword
+        $ = "netstat -an" fullword
+        $ = "php://"
+        $ = "ps -aux" fullword
+        $ = "rootkit" fullword nocase
+        $ = "slowloris" fullword nocase
+        $ = "suhosin" fullword
+        $ = "sun-tzu" fullword nocase // Because quotes from the Art of War is mandatory for any cool webshell.
+    $ = /trojan (payload)?/
+        $ = "uname -a" fullword
+        $ = "visbot" nocase fullword
+        $ = "warez" fullword nocase
+        $ = "whoami" fullword
+        $ = /(r[e3]v[e3]rs[e3]|w[3e]b|cmd)\s*sh[e3]ll/ nocase
+        $ = /-perm -0[24]000/ // find setuid files
+        $ = /\/bin\/(ba)?sh/ fullword
+        $ = /hack(ing|er|ed)/ nocase
+        $ = /(safe_mode|open_basedir) bypass/ nocase
+        $ = /xp_(execresultset|regenumkeys|cmdshell|filelist)/
+
+        $vbs = /language\s*=\s*vbscript/ nocase
+        $asp = "scripting.filesystemobject" nocase
+
+    condition:
+        (IRC or 2 of them) and not IsWhitelisted
+}
+
+rule Websites
+{
+    strings:
+        $ = "1337day.com" nocase
+        $ = "antichat.ru" nocase
+        $ = "b374k" nocase
+        $ = "ccteam.ru" nocase
+        $ = "crackfor" nocase
+        $ = "darkc0de" nocase
+        $ = "egyspider.eu" nocase
+        $ = "exploit-db.com" nocase
+        $ = "fopo.com.ar" nocase  /* Free Online Php Obfuscator */
+        $ = "hashchecker.com" nocase
+        $ = "hashkiller.com" nocase
+        $ = "md5crack.com" nocase
+        $ = "md5decrypter.com" nocase
+        $ = "milw0rm.com" nocase
+        $ = "milw00rm.com" nocase
+        $ = "packetstormsecurity" nocase
+        $ = "pentestmonkey.net" nocase
+        $ = "phpjiami.com" nocase
+        $ = "rapid7.com" nocase
+        $ = "securityfocus" nocase
+        $ = "shodan.io" nocase
+        $ = "github.com/b374k/b374k" nocase
+        $ = "mumaasp.com" nocase
+
+    condition:
+        (any of them) and not IsWhitelisted
+}
+