Jump to content

Leaderboard

Popular Content

Showing content with the highest reputation on 04/18/18 in all areas

  1. Da, se poate trai, dar doresc sa precizez anumite lucruri: - trebuie cunostinte tehnice foarte avansate. Nu poti sa gasesti vulnerabilitati cand nu stii cum functioneaza un lucru in cele mai mici detalii. - trebuie timp investit constant in a fi la curent cu tot ce se intampla domeniul securitatii - cei mai buni din domeniu (acei 1% care traiesc doar din asta), au ajuns aici facand acest lucru din pasiune, curiozitate, motivatie. Nu o sa te duca prea departe doar dorinta de a castiga bani. Nu o sa fie un castig constant ca si la un loc de munca, uneori o sa fie bani (mai multi sau mai putini), alteori nu o sa fie. Deci s-ar putea sa apara sentimentul de nesiguranta in aceste perioade, si n-o sa mai faci din placere. Cel mai bine gandim cand nu avem grija zilei de maine. Eu as recomanda pentru inceput sa faci asta in timpul liber, sa vezi daca iti place si cum merge treaba. E la fel ca si cu freelancingul, nu iti poti da demisia si sa treci direct in freelancing, pana nu ai o plasa de siguranta pentru cazuri neprevazute. Testezi apele si iti cam dai seama ce ai putea sa faci pe viitor. https://hackerone.com/leaderboard/all-time - Topul celor din hackerone(bug bounty platform). Poti sa-i urmaresti pe twitter sau sa le citesti blogurile https://www.youtube.com/playlist?list=PLZaG0MNecryP55u43LWqHy5MADcvLjnL- - Interviuri foarte interesante cu top hunters (unii fac parte si din topul de mai sus)
    4 points
  2. O lista cu referinte catre blog-uri ce contin write-up-uri despre bug-uri gasite in companii ce au un program bug bounty. https://github.com/ngalongc/bug-bounty-reference
    1 point
  3. Webapps occasionaly need to create tokens that are hard to guess. For example for session tokens or CSRF tokens, or in forgot password functionality where you get a token mailed to reset your password. These tokens should be cryptographically secure, but are often made by calling rand() multiple times and transforming the output to a string. This post will explore how hard it is to predict a token made with rand(). How rand works In PHP, the function rand() creates pseudorandom numbers. The initial state of the random number generator (the seed) is set with srand. If you don’t call srand yourself, PHP seeds the random number generator with some hard to guess number when you call rand. The seed passed to srand totally determines the string of numbers that rand will generate. The random number generator keeps a state that is initially set by srand and then changed every time you call rand. This state is specific to the process, so two processes typically return different numbers for rand. On Windows this state has a size of 32 bits and can be directly set using srand. On Linux the state is 1024 bits. Our example program Our example program is EZChatter, a small toy program put together in a day. It does use CSRF tokens, but does not a very good job at creating them securily: public static function gen($len = 5) { $token = ''; while($len--){ $choose = rand(0, 2); if ($choose === 0) $token .= chr(rand(ord('A'), ord('Z'))); else if($choose === 1) $token .= chr(rand(ord('a'), ord('z'))); else $token .= chr(rand(ord('0'), ord('9'))); } return $token; } As you can see it first calls rand to determine whether to use an uppercase letter, lowercase letter or number, and then again to pick a specific letter or number. Every time we request the index.php page we get a new CSRF token, so we can request as many as we want. Our job is to predict tokens that have been handed out to other users, so we can do a CSRF attack on them. Seed cracking As we said the random number series is totally defined by the seed, so we can simply try every possible number as argument for srand to get the random number generator in the right state. Note that on Linux this will only work if the server process is fresh. If the server process has already seen a lot of rand calls, we need to do the same amount in our cracking program to get the same state. On Windows, the state of the random number generator is the same as the argument to srand, so you don’t need a fresh process. If we got a token from a fresh process, the following PHP script can be used to crack it: for ($i = 0; $i < PHP_INT_MAX; $i++) { srand($i); if (Token::gen(10) == "2118Jx9w3e") { die("Found: $i \n"); } } To search the 4294967295 possible arguments to srand, this will take approximately 12 hours. However, since PHP just calls the glibc rand function, we can reimplement the PHP code as C and speed things up. I have made two versions, one that calls the glibc rand and one that mimics the Windows rand. It is basically the PHP code from token.php, a copy paste of some macro’s from PHP’s ext/standard/rand.c, and a loop to go through every possible seed. This will take about 10 minutes for the Windows version and a couple of hours for the Linux version. Once completed, you have the random number generator in the same state and you can keep generating the same tokens as on the server. By comparing your own generated tokens with the tokens the server returns you know which tokens have been handed out to other users, and you can start your attack. State cracking on Linux On Windows, cracking the argument to srand and cracking the state of the random number generator turn out to be the same thing, but on Linux they are different. The glibc rand() keeps a series of numbers, and determines the next state like this: state = state[i-3] + state[i-31] return state >> 1 So every output is approximately the summed output from 3 and 31 calls ago. Consider the following series of tokens: 6ZF5kNgonV 9h3byovpGR gGt0A94U92 Now, the next rand will be determining whether it will be an uppercase letter, lowercase letter or number. This is determined by the outcomes of rand 3 and 31 calls ago. That’s the last 9 in gGt0A94U92 and the y in 9h3byovpGR. So we expect the next output of rand(0, 2) to be approximately ⌊10/10 + 25/26 × 3⌋ = 2 mod 3, so that means we get a number. Let’s see if we can predict that number. The next calls to rand that determines the number is determined by the rand from 3 calls ago, a number, and the rand of 31 calls ago, a lowercase letter. The number will thus be between ⌊2/3 + 1/3 × 10⌋ = 0 mod 10 and ⌊3/3 + 2/3 × 10⌋ = 6 mod 10. We thus expect the number to be between 0 and 6. It turns out to be 4: 43J2d2ew31 As you can see we can not accurately predict the next token using this method, but it is also clear that the we can predict so much about it that you can hardly call it random. It may also be possible to crack the whole state of the glibc random number generator given enough tokens, although I have not tried this. Conclusion Tokens should be created using a cryptographically secure random number generator. If they are made with rand, the state of the random number generator can be cracked trivially in many cases, and tokens can be predicted. On Linux it is a little bit harder to predict tokens, but this does still not give secure tokens. The random number generator on Windows is particularly easy to exploit, since any state of the random number generator can be cracked within minutes. Sursa
    1 point
  4. Esti prost facut gramada. P.S. Marea majoritate importanta pe forum nu se infecteaza din greseala cu malware, ca tu esti prost ( vezi sus ) nu e problema noastra. P.P.S. Aparent, cu intelectul tau limitat, consideri ca acest forum este unul de frauda sau incurajeaza in vreun fel frauda. In acest caz, nu vad de ce ai mai beneficia de privilegiul de membru. Vezi-ti de dezamagirile tale in viata reala, si lasa baietii de aici in pace.
    1 point
  5. da-ma dracu' ce periculos esti tu. Esti pe un forum de IT si cam orice tip de securitate IT dar te apuca smecheria cand citesti despre asa ceva, esti cam ipocrit.
    1 point
  6. Pentru mine asta e o prostie de copii dusi cu pluta. Voua v-ar place ca cineva sa va infecteze cu o prostie de genul asta si sa va controleze dispozitivul si sa va vada toate cele?, eu daca as cunoaste oameni care infecteaza telefoane cu acel program i-as da in judecata, si daca nu s-ar rezolva problema, m-as ocupa de el personal ca sa nu mai faca asa ceva .
    -1 points
  7. Nu fii handicapat. Tie ti-ar place ca intr-o zi sa te infectezi cu un RAT din asta si sa vada un bou toate conversatiile tale, apelurile, sms-urile si altele?. Ce ai face daca s-ar intampla, ai sta ca un bou sau ai vrea sa afli cine e individul ca sa-l pui la punct?........oricum asta nu e un forum de securitate, asta este un forum de frauda, se permite orice, si cand apare unul cu carding sau skimming ia ban, dar pe forum altii pun alte prostii care sunt echivalente cu frauda. Nu sunt nici un ipocrit, ala e adevarul care l-as face si toti ar face la fel doar ca unii ori nu o sa recunoasca sau o sa se abtina............DE FACUT RAU LA TOTI VA PLACE, DAR CAND VINE VORBA SA VA GANDITI CUM AR FI DACA VOUA V-AR FACE ALTUL ASA CEVA NU MAI SUNTETI ASA SMECHERI.
    -1 points
  8. Conturile ciordite ce sunt?!, nologinurile ce sunt?!, tutorialele cum sa ciordesti conturi ce sunt?!, coailii stealer ce este?! printre alte cacaturi de-a voastre...FRAUDA TOTALA, SI VA PLANGETI DE CARDERI...........................ia sa-mi stearga careva contul asta ca aici sunt numai handicapati romani
    -1 points
  9. When already bitcoin goes up
    -1 points
  10. Cu acest micut soft puteti trimite sms-uri nelimitate si gratuite catre orice numar mobil (doar romania) Daca nu aveti incredere in acest soft...puteti trimite sms-uri si online pe www.opa-sms.ro Download PS:Daca apasati butonul trimite credeti ca imi va cadea serverul ? nu puteti da atack pS:softul a fost dezactivat activ doar pe site
    -2 points
×
×
  • Create New...