文件上传

文件上传

.user.ini 的妙用原理

   .user.ini 中两个中的配置是 auto_prepend_file ​和 auto_append_file

  意思就是:我们指定一个文件(如 1.jpg),那么该文件就会被包含在要执行的 php 文件中(如 index.php)

  区别在于 auto_prepend_file 是在文件插入,auto_append_file 在文件最插入。

  user.ini 可以把指定的一个文件包含到这个目录下任意一个会以 php 执行的文件中(比如 index.php、test.php),当你访问 index.php 后这个被你指定的文件,无论后缀是什么都会以 php 的方式进行读取,所以可以绕过后端检测

eg:

  首先上传 .user.ini

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auto_prepend_file=shell.png

  然后再上传 shell.png

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一句话木马

  ** 注意:最后要访问/upload/index.php, 而非文件目录 **

经典过滤

  1. 更改 js 代码绕过前端过滤

  2. 文件后缀,大小写、如果是 apache,可以多写一个不能解析的后缀,php.xxxx

  3. 如果后端是通过 content-type 来进行校验的,可以将 content-type 修改为可以上传的文件的类型值,后端代码对应为 $_FILE(“file”)

  4. 过滤 php ​使用短标签

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    =
  5. 绕过空格:使用转义字符 \t ​或者 进行 URL 编码

  6. 绕过 []​:在 php 中大括号和中括号等价,可以使用 {} ​来绕过对中括号的过滤

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    {}
  7. 绕过 [] ​和 {}​:使用 array_pop() ​函数,括号内部写传参的形式,array_pop($_POST);​,以字符串的形式返回执行语句,可以配合 eval() ​函数进行使用

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    <?=eval(array_pop($_POST['1']);&1=system("待执行命令"));?>
  8. 绕过对 ; ​的过滤:最后一句不用带分号,中间的分号可以用 ?> ​来进行过滤

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Content-type

  内容类型,一般指的是网页中存在的 Content-Type,用于定义网络文件的类型和网页的编码,决定接收方以什么形式,什么编码解读这个文件

  ContentType 属性指定响应的 HTTP 内容类型。如果未指定 ContentType,默认为 TEXT/HTML

  application/octet-stream 字节流,浏览器处理字节流的默认方式就是下载

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最重要的
1. application/octet-stream 字节流,浏览器处理字节流的默认方式就是下载
2. image/png 图片类型,将会以图片类型解析

"."="application/octet-stream"".001"="application/x-001"".301"="application/x-301"".323"="text/h323"".906"="application/x-906"".907"="drawing/907"".a11"="application/x-a11"".acp"="audio/x-mei-aac"".ai"="application/postscript"".aif"="audio/aiff"".aifc"="audio/aiff"".aiff"="audio/aiff"".anv"="application/x-anv"".asa"="text/asa"".asf"="video/x-ms-asf"".asp"="text/asp"".asx"="video/x-ms-asf"".au"="audio/basic"".avi"="video/avi"".awf"="application/vnd.adobe.workflow"".biz"="text/xml"".bmp"="application/x-bmp"".bot"="application/x-bot"".c4t"="application/x-c4t"".c90"="application/x-c90"".cal"="application/x-cals"".cat"="application/s-pki.seccat"".cdf"="application/x-netcdf"".cdr"="application/x-cdr"".cel"="application/x-cel"".cer"="application/x-x509-ca-cert"".cg4"="application/x-g4"".cgm"="application/x-cgm"".cit"="application/x-cit"".class"="java/"
".cml"="text/xml"
".cmp"="application/x-cmp"
".cmx"="application/x-cmx"
".cot"="application/x-cot"
".crl"="application/pkix-crl"
".crt"="application/x-x509-ca-cert"
".csi"="application/x-csi"
".css"="text/css"
".cut"="application/x-cut"
".dbf"="application/x-dbf"
".dbm"="application/x-dbm"
".dbx"="application/x-dbx"
".dcd"="text/xml"
".dcx"="application/x-dcx"
".der"="application/x-x509-ca-cert"
".dgn"="application/x-dgn"
".dib"="application/x-dib"
".dll"="application/x-msdownload"
".doc"="application/msword"
".dot"="application/msword"
".drw"="application/x-drw"
".dtd"="text/xml"
".dwf"="Model/vnd.dwf"
".dwf"="application/x-dwf"
".dwg"="application/x-dwg"
".dxb"="application/x-dxb"
".dxf"="application/x-dxf"
".edn"="application/vnd.adobe.edn"
".emf"="application/x-emf"
".eml"="message/rfc822"
".ent"="text/xml"
".epi"="application/x-epi"
".eps"="application/x-ps"
".eps"="application/postscript"
".etd"="application/x-ebx"
".exe"="application/x-msdownload"
".fax"="image/fax"
".fdf"="application/vnd.fdf"
".fif"="application/fractals"
".fo"="text/xml"
".frm"="application/x-frm"
".g4"="application/x-g4"
".gbr"="application/x-gbr"
".gcd"="application/x-gcd"
".gif"="image/gif"
".gl2"="application/x-gl2"
".gp4"="application/x-gp4"
".hgl"="application/x-hgl"
".hmr"="application/x-hmr"
".hpg"="application/x-hpgl"
".hpl"="application/x-hpl"
".hqx"="application/mac-binhex40"
".hrf"="application/x-hrf"
".hta"="application/hta"
".htc"="text/x-component"
".htm"="text/html"
".html"="text/html"
".htt"="text/webviewhtml"
".htx"="text/html"
".icb"="application/x-icb"
".ico"="image/x-icon"
".ico"="application/x-ico"
".iff"="application/x-iff"
".ig4"="application/x-g4"
".igs"="application/x-igs"
".iii"="application/x-iphone"
".img"="application/x-img"
".ins"="application/x-internet-signup"
".isp"="application/x-internet-signup"
".IVF"="video/x-ivf"
".java"="java/*"
".jfif"="image/jpeg"
".jpe"="image/jpeg"
".jpe"="application/x-jpe"
".jpeg"="image/jpeg"
".jpg"="image/jpeg"
".jpg"="application/x-jpg"
".js"="application/x-javascript"
".jsp"="text/html"
".la1"="audio/x-liquid-file"
".lar"="application/x-laplayer-reg"
".latex"="application/x-latex"
".lavs"="audio/x-liquid-secure"
".lbm"="application/x-lbm"
".lmsff"="audio/x-la-lms"
".ls"="application/x-javascript"
".ltr"="application/x-ltr"
".m1v"="video/x-mpeg"
".m2v"="video/x-mpeg"
".m3u"="audio/mpegurl"
".m4e"="video/mpeg4"
".mac"="application/x-mac"
".man"="application/x-troff-man"
".math"="text/xml"
".mdb"="application/msaccess"
".mdb"="application/x-mdb"
".mfp"="application/x-shockwave-flash"
".mht"="message/rfc822"
".mhtml"="message/rfc822"
".mi"="application/x-mi"
".mid"="audio/mid"
".midi"="audio/mid"
".mil"="application/x-mil"
".mml"="text/xml"
".mnd"="audio/x-musicnet-download"
".mns"="audio/x-musicnet-stream"
".mocha"="application/x-javascript"
".movie"="video/x-sgi-movie"
".mp1"="audio/mp1"
".mp2"="audio/mp2"
".mp2v"="video/mpeg"
".mp3"="audio/mp3"
".mp4"="video/mp4"
".mpa"="video/x-mpg"
".mpd"="application/-project"
".mpe"="video/x-mpeg"
".mpeg"="video/mpg"
".mpg"="video/mpg"
".mpga"="audio/rn-mpeg"
".mpp"="application/-project"
".mps"="video/x-mpeg"
".mpt"="application/-project"
".mpv"="video/mpg"
".mpv2"="video/mpeg"
".mpw"="application/s-project"
".mpx"="application/-project"
".mtx"="text/xml"
".mxp"="application/x-mmxp"
".net"="image/pnetvue"
".nrf"="application/x-nrf"
".nws"="message/rfc822"
".odc"="text/x-ms-odc"
".out"="application/x-out"
".p10"="application/pkcs10"
".p12"="application/x-pkcs12"
".p7b"="application/x-pkcs7-certificates"
".p7c"="application/pkcs7-mime"
".p7m"="application/pkcs7-mime"
".p7r"="application/x-pkcs7-certreqresp"
".p7s"="application/pkcs7-signature"
".pc5"="application/x-pc5"
".pci"="application/x-pci"
".pcl"="application/x-pcl"
".pcx"="application/x-pcx"
".pdf"="application/pdf"
".pdx"="application/vnd.adobe.pdx"
".pfx"="application/x-pkcs12"
".pgl"="application/x-pgl"
".pic"="application/x-pic"
".pko"="application-pki.pko"
".pl"="application/x-perl"
".plg"="text/html"
".pls"="audio/scpls"
".plt"="application/x-plt"
".png"="image/png"
".png"="application/x-png"
".pot"="applications-powerpoint"
".ppa"="application/vs-powerpoint"
".ppm"="application/x-ppm"
".pps"="application-powerpoint"
".ppt"="applications-powerpoint"
".ppt"="application/x-ppt"
".pr"="application/x-pr"
".prf"="application/pics-rules"
".prn"="application/x-prn"
".prt"="application/x-prt"
".ps"="application/x-ps"
".ps"="application/postscript"
".ptn"="application/x-ptn"
".pwz"="application/powerpoint"
".r3t"="text/vnd.rn-realtext3d"
".ra"="audio/vnd.rn-realaudio"
".ram"="audio/x-pn-realaudio"
".ras"="application/x-ras"
".rat"="application/rat-file"
".rdf"="text/xml"
".rec"="application/vnd.rn-recording"
".red"="application/x-red"
".rgb"="application/x-rgb"
".rjs"="application/vnd.rn-realsystem-rjs"
".rjt"="application/vnd.rn-realsystem-rjt"
".rlc"="application/x-rlc"
".rle"="application/x-rle"
".rm"="application/vnd.rn-realmedia"
".rmf"="application/vnd.adobe.rmf"
".rmi"="audio/mid"
".rmj"="application/vnd.rn-realsystem-rmj"
".rmm"="audio/x-pn-realaudio"
".rmp"="application/vnd.rn-rn_music_package"
".rms"="application/vnd.rn-realmedia-secure"
".rmvb"="application/vnd.rn-realmedia-vbr"
".rmx"="application/vnd.rn-realsystem-rmx"
".rnx"="application/vnd.rn-realplayer"
".rp"="image/vnd.rn-realpix"
".rpm"="audio/x-pn-realaudio-plugin"
".rsml"="application/vnd.rn-rsml"
".rt"="text/vnd.rn-realtext"
".rtf"="application/msword"
".rtf"="application/x-rtf"
".rv"="video/vnd.rn-realvideo"
".sam"="application/x-sam"
".sat"="application/x-sat"
".sdp"="application/sdp"
".sdw"="application/x-sdw"
".sit"="application/x-stuffit"
".slb"="application/x-slb"
".sld"="application/x-sld"
".slk"="drawing/x-slk"
".smi"="application/smil"
".smil"="application/smil"
".smk"="application/x-smk"
".snd"="audio/basic"
".sol"="text/plain"
".sor"="text/plain"
".spc"="application/x-pkcs7-certificates"
".spl"="application/futuresplash"
".spp"="text/xml"
".ssm"="application/streamingmedia"
".sst"="application-pki.certstore"
".stl"="application/-pki.stl"
".stm"="text/html"
".sty"="application/x-sty"
".svg"="text/xml"
".swf"="application/x-shockwave-flash"
".tdf"="application/x-tdf"
".tg4"="application/x-tg4"
".tga"="application/x-tga"
".tif"="image/tiff"
".tif"="application/x-tif"
".tiff"="image/tiff"
".tld"="text/xml"
".top"="drawing/x-top"
".torrent"="application/x-bittorrent"
".tsd"="text/xml"
".txt"="text/plain"
".uin"="application/x-icq"
".uls"="text/iuls"
".vcf"="text/x-vcard"
".vda"="application/x-vda"
".vdx"="application/vnd.visio"
".vml"="text/xml"
".vpg"="application/x-vpeg005"
".vsd"="application/vnd.visio"
".vsd"="application/x-vsd"
".vss"="application/vnd.visio"
".vst"="application/vnd.visio"
".vst"="application/x-vst"
".vsw"="application/vnd.visio"
".vsx"="application/vnd.visio"
".vtx"="application/vnd.visio"
".vxml"="text/xml"
".wav"="audio/wav"
".wax"="audio/x-ms-wax"
".wb1"="application/x-wb1"
".wb2"="application/x-wb2"
".wb3"="application/x-wb3"
".wbmp"="image/vnd.wap.wbmp"
".wiz"="application/msword"
".wk3"="application/x-wk3"
".wk4"="application/x-wk4"
".wkq"="application/x-wkq"
".wks"="application/x-wks"
".wm"="video/x-ms-wm"
".wma"="audio/x-ms-wma"
".wmd"="application/x-ms-wmd"
".wmf"="application/x-wmf"
".wml"="text/vnd.wap.wml"
".wmv"="video/x-ms-wmv"
".wmx"="video/x-ms-wmx"
".wmz"="application/x-ms-wmz"
".wp6"="application/x-wp6"
".wpd"="application/x-wpd"
".wpg"="application/x-wpg"
".wpl"="application/-wpl"
".wq1"="application/x-wq1"
".wr1"="application/x-wr1"
".wri"="application/x-wri"
".wrk"="application/x-wrk"
".ws"="application/x-ws"
".ws2"="application/x-ws"
".wsc"="text/scriptlet"
".wsdl"="text/xml"
".wvx"="video/x-ms-wvx"
".xdp"="application/vnd.adobe.xdp"
".xdr"="text/xml"
".xfd"="application/vnd.adobe.xfd"
".xfdf"="application/vnd.adobe.xfdf"
".xhtml"="text/html"
".xls"="application/-excel"
".xls"="application/x-xls"
".xlw"="application/x-xlw"
".xml"="text/xml"
".xpl"="audio/scpls"
".xq"="text/xml"
".xql"="text/xml"
".xquery"="text/xml"
".xsd"="text/xml"
".xsl"="text/xml"
".xslt"="text/xml"
".xwd"="application/x-xwd"
".x_b"="application/x-x_b"
".x_t"="application/x-x_t"
Office2007对应的值:
"application/vnd.openxmlformats-officedocument.wordprocessingml.template" (for .docx files)
"application/vnd.openxmlformats-officedocument.presentationml.presentation" (for .pptx files)
"application/vnd.openxmlformats-officedocument.presentationml.slideshow" (for .ppsx files)
"application/vnd.openxmlformats-officedocument.presentationml.template" (for .potx files)
"application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" (for .xlsx files)
"application/vnd.openxmlformats-officedocument.spreadsheetml.template" (for .xltx files)
相对于Office2003是这样的
Response.ContentType = "application/vnd.ms-excel"

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