WEBSHELL_JSP_NetSpy
Description
JSP netspy webshell
Query · yara
strings:
$scan1 = "scan" nocase wide ascii
$scan2 = "port" nocase wide ascii
$scan3 = "web" fullword nocase wide ascii
$scan4 = "proxy" fullword nocase wide ascii
$scan5 = "http" fullword nocase wide ascii
$scan6 = "https" fullword nocase wide ascii
$write1 = "os.write" fullword wide ascii
$write2 = "FileOutputStream" fullword wide ascii
$write3 = "PrintWriter" fullword wide ascii
$http = "java.net.HttpURLConnection" fullword wide ascii
//strings from private rule capa_jsp_safe
$cjsp_short1 = "<%" ascii wide
$cjsp_short2 = "%>" wide ascii
$cjsp_long1 = "<jsp:" ascii wide
$cjsp_long2 = /language=[\"']java[\"\']/ ascii wide
// JSF
$cjsp_long3 = "/jstl/core" ascii wide
$cjsp_long4 = "<%@p" nocase ascii wide
$cjsp_long5 = "<%@ " nocase ascii wide
$cjsp_long6 = "<% " ascii wide
$cjsp_long7 = "< %" ascii wide
//strings from private rule capa_jsp_input
// request.getParameter
$input1 = "getParameter" fullword ascii wide
// request.getHeaders
$input2 = "getHeaders" fullword ascii wide
$input3 = "getInputStream" fullword ascii wide
$input4 = "getReader" fullword ascii wide
$req1 = "request" fullword ascii wide
$req2 = "HttpServletRequest" fullword ascii wide
$req3 = "getRequest" fullword ascii wide
condition:
filesize < 30KB and (
$cjsp_short1 at 0 or
any of ( $cjsp_long* ) or
($cjsp_short1 and $cjsp_short2 in ( filesize-100..filesize )) or
(
$cjsp_short2 and (
$cjsp_short1 in ( 0..1000 ) or
$cjsp_short1 in ( filesize-1000..filesize )
)
)
)
and (
any of ( $input* ) and
any of ( $req* )
)
and 4 of ( $scan* ) and 1 of ( $write* ) and $http
}
rule WEBSHELL_JSP_By_String
{
meta:
description = "JSP Webshells which contain unique strings, lousy rule for low hanging fruits. Most are catched by other rules in here but maybe these catch different versions."
license = "Detection Rule License 1.1 https://github.com/Neo23x0/signature-base/blob/master/LICENSE"
author = "Arnim Rupp (https://github.com/ruppde)"
reference = "Internal Research"
score = 75
date = "2021/01/09"
modified = "2025-08-18"
hash = "e9060aa2caf96be49e3b6f490d08b8a996c4b084"
hash = "4c2464503237beba54f66f4a099e7e75028707aa"
hash = "06b42d4707e7326aff402ecbb585884863c6351a"
hash = "dada47c052ec7fcf11d5cfb25693bc300d3df87de182a254f9b66c7c2c63bf2e"
hash = "f9f6c696c1f90df6421cd9878a1dec51a62e91b4b4f7eac4920399cb39bc3139"
hash = "f1d8360dc92544cce301949e23aad6eb49049bacf9b7f54c24f89f7f02d214bb"
hash = "1d1f26b1925a9d0caca3fdd8116629bbcf69f37f751a532b7096a1e37f4f0076"
hash = "850f998753fde301d7c688b4eca784a045130039512cf51292fcb678187c560b"
id = "8d64e40b-5583-5887-afe1-b926d9880913"
strings:
$jstring1 = "<title>Boot Shell</title>" wide ascii
$jstring2 = "String oraPWD=\"" wide ascii
$jstring3 = "Owned by Chinese Hackers!" wide ascii
$jstring4 = "AntSword JSP" wide ascii
$jstring5 = "JSP Webshell</" wide ascii
$jstring6 = "motoME722remind2012" wide ascii
$jstring7 = "EC(getFromBase64(toStringHex(request.getParameter(\"password" wide ascii
$jstring8 = "http://jmmm.com/web/index.jsp" wide ascii
$jstring9 = "list.jsp = Directory & File View" wide ascii
$jstring10 = "jdbcRowSet.setDataSourceName(request.getParameter(" wide ascii
$jstring11 = "Mr.Un1k0d3r RingZer0 Team" wide ascii
$jstring12 = "MiniWebCmdShell" fullword wide ascii
$jstring13 = "pwnshell.jsp" fullword wide ascii
$jstring14 = "session set <key> <value> [class]<br>" wide ascii
$jstring15 = "Runtime.getRuntime().exec(request.getParameter(" nocase wide ascii
$jstring16 = "GIF98a<%@page" wide ascii
$jstring17 = "Tas9er" fullword wide ascii
$jstring18 = "uu0028\\u" wide ascii //obfuscated /
$jstring19 = "uu0065\\u" wide ascii //obfuscated e
$jstring20 = "uu0073\\u" wide ascii //obfuscated s
$jstring21 = /\\uuu{0,50}00/ wide ascii //obfuscated via javas unlimited amount of u in \uuuuuu
$jstring22 = /[\w\.]\\u(FFFB|FEFF|FFF9|FFFA|200C|202E|202D)[\w\.]/ wide ascii // java ignores the unicode Interlinear Annotation Terminator inbetween any command
$jstring23 = "\"e45e329feb5d925b\"" wide ascii
$jstring24 = "u<![CDATA[n" wide ascii
//strings from private rule capa_jsp_safe
$cjsp_short1 = "<%" ascii wide
$cjsp_short2 = "%>" wide ascii
$cjsp_long1 = "<jsp:" ascii wide
$cjsp_long2 = /language=[\"']java[\"\']/ ascii wide
// JSF
$cjsp_long3 = "/jstl/core" ascii wide
$cjsp_long4 = "<%@p" nocase ascii wide
$cjsp_long5 = "<%@ " nocase ascii wide
$cjsp_long6 = "<% " ascii wide
$cjsp_long7 = "< %" ascii wide
//strings from private rule capa_bin_files
$dex1 = "dex\n0"
$dex2 = "dey\n0"
$pack = { 50 41 43 4b 00 00 00 02 00 }
condition:
//any of them or
not (
uint16(0) == 0x5a4d or
$dex1 at 0 or
$dex2 at 0 or
$pack at 0 or
// fp on jar with zero compression
uint16(0) == 0x4b50
) and
(
(
filesize < 100KB and
(
$cjsp_short1 at 0 or
any of ( $cjsp_long* ) or
($cjsp_short1 and $cjsp_short2 in ( filesize-100..filesize )) or
(
$cjsp_short2 and (
$cjsp_short1 in ( 0..1000 ) or
$cjsp_short1 in ( filesize-1000..filesize )
)
)
)
and any of ( $jstring* )
) or (
filesize < 500KB and
(
#jstring21 > 20 or
$jstring18 or
$jstring19 or
$jstring20
)
)
)
}
rule WEBSHELL_JSP_Input_Upload_Write
{
meta:
description = "JSP uploader which gets input, writes files and contains \"upload\""
license = "Detection Rule License 1.1 https://github.com/Neo23x0/signature-base/blob/master/LICENSE"
author = "Arnim Rupp (https://github.com/ruppde)"
reference = "Internal Research"
score = 75
date = "2021/01/24"
modified = "2024-12-09"
hash = "ef98ca135dfb9dcdd2f730b18e883adf50c4ab82"
hash = "583231786bc1d0ecca7d8d2b083804736a3f0a32"
hash = "19eca79163259d80375ebebbc440b9545163e6a3"
id = "bbf26edd-88b7-5ec5-a16e-d96a086dcd19"
strings:
$upload = "upload" nocase wide ascii
$write1 = "os.write" fullword wide ascii
$write2 = "FileOutputStream" fullword wide ascii
//strings from private rule capa_jsp_safe
$cjsp_short1 = "<%" ascii wide
$cjsp_short2 = "%>" wide ascii
$cjsp_long1 = "<jsp:" ascii wide
$cjsp_long2 = /language=[\"']java[\"\']/ ascii wide
// JSF
$cjsp_long3 = "/jstl/core" ascii wide
$cjsp_long4 = "<%@p" nocase ascii wide
$cjsp_long5 = "<%@ " nocase ascii wide
$cjsp_long6 = "<% " ascii wide
$cjsp_long7 = "< %" ascii wide
//strings from private rule capa_jsp_input
// request.getParameter
$input1 = "getParameter" fullword ascii wide
// request.getHeaders
$input2 = "getHeaders" fullword ascii wide
$input3 = "getInputStream" fullword ascii wide
$input4 = "getReader" fullword ascii wide
$req1 = "request" fullword ascii wide
$req2 = "HttpServletRequest" fullword ascii wide
$req3 = "getRequest" fullword ascii wide
condition:
filesize < 10KB and (
$cjsp_short1 at 0 or
any of ( $cjsp_long* ) or
($cjsp_short1 and $cjsp_short2 in ( filesize-100..filesize )) or
(
$cjsp_short2 and (
$cjsp_short1 in ( 0..1000 ) or
$cjsp_short1 in ( filesize-1000..filesize )
)
)
)
and (
any of ( $input* ) and
any of ( $req* )
)
and $upload and 1 of ( $write* )
}
rule WEBSHELL_Generic_OS_Strings : FILE {
meta:
description = "typical webshell strings"
license = "Detection Rule License 1.1 https://github.com/Neo23x0/signature-base/blob/master/LICENSE"
author = "Arnim Rupp (https://github.com/ruppde)"
reference = "Internal Research"
date = "2021/01/12"
modified = "2024-12-09"
score = 50
hash = "d5bfe40283a28917fcda0cefd2af301f9a7ecdad"
hash = "fd45a72bda0a38d5ad81371d68d206035cb71a14"
hash = "b4544b119f919d8cbf40ca2c4a7ab5c1a4da73a3"
hash = "569259aafe06ba3cef9e775ee6d142fed6edff5f"
hash = "48909d9f4332840b4e04b86f9723d7427e33ac67"
hash = "0353ae68b12b8f6b74794d3273967b530d0d526f"
id = "ea85e415-4774-58ac-b063-0f5eb535ec49"
strings:
$fp1 = "http://evil.com/" wide ascii
$fp2 = "denormalize('/etc/shadow" wide ascii
$fp3 = "vim.org>"
//strings from private rule capa_asp
$tagasp_short1 = /<%[^"]/ wide ascii
// also looking for %> to reduce fp (yeah, short atom but seldom since special chars)
$tagasp_short2 = "%>" wide ascii
// classids for scripting host etc
$tagasp_classid1 = "72C24DD5-D70A-438B-8A42-98424B88AFB8" nocase wide ascii
$tagasp_classid2 = "F935DC22-1CF0-11D0-ADB9-00C04FD58A0B" nocase wide ascii
$tagasp_classid3 = "093FF999-1EA0-4079-9525-9614C3504B74" nocase wide ascii
$tagasp_classid4 = "F935DC26-1CF0-11D0-ADB9-00C04FD58A0B" nocase wide ascii
$tagasp_classid5 = "0D43FE01-F093-11CF-8940-00A0C9054228" nocase wide ascii
$tagasp_long10 = "<%@ " wide ascii
// <% eval
$tagasp_long11 = /<% \w/ nocase wide ascii
$tagasp_long12 = "<%ex" nocase wide ascii
$tagasp_long13 = "<%ev" nocase wide ascii
// <%@ LANGUAGE = VBScript.encode%>
// <%@ Language = "JScript" %>
// <%@ WebHandler Language="C#" class="Handler" %>
// <%@ WebService Language="C#" Class="Service" %>
// <%@Page Language="Jscript"%>
// <%@ Page Language = Jscript %>
// <%@PAGE LANGUAGE=JSCRIPT%>
// <%@ Page Language="Jscript" validateRequest="false" %>
// <%@ Page Language = Jscript %>
// <%@ Page Language="C#" %>
// <%@ Page Language="VB" ContentType="text/html" validaterequest="false" AspCompat="true" Debug="true" %>
// <script runat="server" language="JScript">
// <SCRIPT RUNAT=SERVER LANGUAGE=JSCRIPT>
// <SCRIPT RUNAT=SERVER LANGUAGE=JSCRIPT>
// <msxsl:script language="JScript" ...
$tagasp_long20 = /<(%|script|msxsl:script).{0,60}language="?(vb|jscript|c#)/ nocase wide ascii
$tagasp_long32 = /<script\s{1,30}runat=/ wide ascii
$tagasp_long33 = /<SCRIPT\s{1,30}RUNAT=/ wide ascii
// avoid hitting php
$php1 = "<?php"
$php2 = "<?="
// avoid hitting jsp
$jsp1 = "=\"java." wide ascii
$jsp2 = "=\"javax." wide ascii
$jsp3 = "java.lang." wide ascii
$jsp4 = "public" fullword wide ascii
$jsp5 = "throws" fullword wide ascii
$jsp6 = "getValue" fullword wide ascii
$jsp7 = "getBytes" fullword wide ascii
$perl1 = "PerlScript" fullword
//strings from private rule capa_php_old_safe
$php_short = "<?" wide ascii
// prevent xml and asp from hitting with the short tag
$no_xml1 = "<?xml version" nocase wide ascii
$no_xml2 = "<?xml-stylesheet" nocase wide ascii
$no_asp1 = "<%@LANGUAGE" nocase wide ascii
$no_asp2 = /<script language="(vb|jscript|c#)/ nocase wide ascii
$no_pdf = "<?xpacket"
// of course the new tags should also match
// already matched by "<?"
$php_new1 = /<\?=[^?]/ wide ascii
$php_new2 = "<?php" nocase wide ascii
$php_new3 = "<script language=\"php" nocase wide ascii
//strings from private rule capa_jsp_safe
$cjsp_short1 = "<%" ascii wide
$cjsp_short2 = "%>" wide ascii
$cjsp_long1 = "<jsp:" ascii wide
$cjsp_long2 = /language=[\"']java[\"\']/ ascii wide
// JSF
$cjsp_long3 = "/jstl/core" ascii wide
$cjsp_long4 = "<%@p" nocase ascii wide
$cjsp_long5 = "<%@ " nocase ascii wide
$cjsp_long6 = "<% " ascii wide
$cjsp_long7 = "< %" ascii wide
//strings from private rule capa_os_strings
// windows = nocase
$w1 = "net localgroup administrators" nocase wide ascii
$w2 = "net user" nocase wide ascii
$w3 = "/add" nocase wide ascii
// linux stuff, case sensitive:
$l1 = "/etc/shadow" wide ascii
$l2 = "/etc/ssh/sshd_config" wide ascii
$take_two1 = "net user" nocase wide ascii
$take_two2 = "/add" nocase wide ascii
condition:
filesize < 70KB and
( (
(
any of ( $tagasp_long* ) or
// TODO : yara_push_private_rules.py doesn't do private rules in private rules yet
any of ( $tagasp_classid* ) or
(
$tagasp_short1 and
$tagasp_short2 in ( filesize-100..filesize )
) or (
$tagasp_short2 and (
$tagasp_short1 in ( 0..1000 ) or
$tagasp_short1 in ( filesize-1000..filesize )
)
)
) and not (
(
any of ( $perl* ) or
$php1 at 0 or
$php2 at 0
) or (
( #jsp1 + #jsp2 + #jsp3 ) > 0 and ( #jsp4 + #jsp5 + #jsp6 + #jsp7 ) > 0
)
)
)
or (
(
(
$php_short in (0..100) or
$php_short in (filesize-1000..filesize)
)
and not any of ( $no_* )
)
or any of ( $php_new* )
)
or (
$cjsp_short1 at 0 or
any of ( $cjsp_long* ) or
($cjsp_short1 and $cjsp_short2 in ( filesize-100..filesize )) or
(
$cjsp_short2 and (
$cjsp_short1 in ( 0..1000 ) or
$cjsp_short1 in ( filesize-1000..filesize )
)
)
)
) and (
filesize < 300KB and
not uint16(0) == 0x5a4d and (
all of ( $w* ) or
all of ( $l* ) or
2 of ( $take_two* )
)
)
and not any of ( $fp* )
}
rule WEBSHELL_In_Image
{
meta:
description = "Webshell in GIF, PNG or JPG"
license = "Detection Rule License 1.1 https://github.com/Neo23x0/signature-base/blob/master/LICENSE"
author = "Arnim Rupp (https://github.com/ruppde)"
reference = "Internal Research"
hash = "d4fde4e691db3e70a6320e78657480e563a9f87935af873a99db72d6a9a83c78"
hash = "84938133ee6e139a2816ab1afc1c83f27243c8ae76746ceb2e7f20649b5b16a4"
hash = "52b918a64afc55d28cd491de451bb89c57bce424f8696d6a94ec31fb99b17c11"
date = "2021/02/27"
modified = "2024-03-11"
score = 55
id = "b1185b69-9b08-5925-823a-829fee6fa4cf"
strings:
$png = { 89 50 4E 47 }
$jpg = { FF D8 FF E0 }
$gif = "GIF8" wide ascii // doesn't make sense for a GIF but some webshells are utf8 :)
$gif2 = "gif89" // not a valid gif but used in webshells
$gif3 = "Gif89" // not a valid gif but used in webshells
// MS access
$mdb = { 00 01 00 00 53 74 }
//$mdb = { 00 01 00 00 53 74 61 6E 64 61 72 64 20 4A 65 74 20 44 42 }
//strings from private rule capa_php_old_safe
$php_short = "<?" wide ascii
// prevent xml and asp from hitting with the short tag
$no_xml1 = "<?xml version" nocase wide ascii
$no_xml2 = "<?xml-stylesheet" nocase wide ascii
$no_asp1 = "<%@LANGUAGE" nocase wide ascii
$no_asp2 = /<script language="(vb|jscript|c#)/ nocase wide ascii
$no_pdf = "<?xpacket"
// of course the new tags should also match
// already matched by "<?"
$php_new1 = /<\?=[^?]/ wide ascii
$php_new2 = "<?php" nocase wide ascii
$php_new3 = "<script language=\"php" nocase wide ascii
//strings from private rule capa_php_payload
// \([^)] to avoid matching on e.g. eval() in comments
$cpayload1 = /\beval[\n\t ]{0,500}(\([^)]|\/\*)/ nocase wide ascii
$cpayload2 = /\bexec[\n\t ]{0,500}(\([^)]|\/\*)/ nocase wide ascii
$cpayload3 = /\bshell_exec[\n\t ]{0,500}(\([^)]|\/\*)/ nocase wide ascii
$cpayload4 = /\bpassthru[\n\t ]{0,500}(\([^)]|\/\*)/ nocase wide ascii
$cpayload5 = /\bsystem[\n\t ]{0,500}(\([^)]|\/\*)/ nocase wide ascii
$cpayload6 = /\bpopen[\n\t ]{0,500}(\([^)]|\/\*)/ nocase wide ascii
$cpayload7 = /\bproc_open[\n\t ]{0,500}(\([^)]|\/\*)/ nocase wide ascii
$cpayload8 = /\bpcntl_exec[\n\t ]{0,500}(\([^)]|\/\*)/ nocase wide ascii
$cpayload9 = /\bassert[\n\t ]{0,500}\([^)0]/ nocase wide ascii
$cpayload10 = /\bpreg_replace[\n\t ]{0,500}\([^\)]{1,100}\/[ismxADSUXju]{0,11}(e|\\x65)/ nocase wide ascii
$cpayload12 = /\bmb_ereg_replace[\t ]{0,500}\([^\)]{1,100}'e'/ nocase wide ascii
$cpayload13 = /\bmb_eregi_replace[\t ]{0,500}\([^\)]{1,100}'e'/ nocase wide ascii
$cpayload20 = /\bcreate_function[\n\t ]{0,500}(\([^)]|\/\*)/ nocase wide ascii
$cpayload21 = /\bReflectionFunction[\n\t ]{0,500}(\([^)]|\/\*)/ nocase wide ascii
$cpayload22 = /fetchall\(PDO::FETCH_FUNC[\n\t ]{0,500}[,