CVE-2001-0167

AT&T WinVNC < 3.3.3r7 - Remote Code Execution via Long rfbConnFailed Reason String

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 2 public exploits for CVE-2001-0167. PoCs published by Metasploit, including Metasploit module exploits/windows/vnc/realvnc_client.

AI-analyzed exploit summary This Metasploit module exploits a buffer overflow in RealVNC 3.3.7 (vncviewer.exe) by sending a maliciously crafted RFB protocol response to trigger remote code execution. The exploit targets specific return addresses for Windows 2000, XP, and 2003.

Description

Buffer overflow in AT&T WinVNC (Virtual Network Computing) client 3.3.3r7 and earlier allows remote attackers to execute arbitrary commands via a long rfbConnFailed packet with a long reason string.

Exploits (2)

exploitdb WORKING POC VERIFIED
by Metasploit · rubyremotewindows
https://www.exploit-db.com/exploits/16489

This Metasploit module exploits a buffer overflow in RealVNC 3.3.7 (vncviewer.exe) by sending a maliciously crafted RFB protocol response to trigger remote code execution. The exploit targets specific return addresses for Windows 2000, XP, and 2003.

Classification
Working Poc 95%
Attack Type
Rce
Complexity
Moderate
Reliability
Reliable
Target: RealVNC 3.3.7
No auth needed
Prerequisites: Network access to the target's VNC port (5900) · Target must be running RealVNC 3.3.7
devstral-2 · analyzed Feb 16, 2026 Full analysis →
metasploit WORKING POC NORMAL
rubypocwin
https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/windows/vnc/realvnc_client.rb

This Metasploit module exploits a buffer overflow in RealVNC 3.3.7 (vncviewer.exe) by sending a maliciously crafted RFB protocol response to trigger remote code execution. It includes target-specific return addresses for Windows 2000, XP, and 2003.

Classification
Working Poc 95%
Attack Type
Rce
Complexity
Moderate
Reliability
Reliable
Target: RealVNC 3.3.7 (vncviewer.exe)
No auth needed
Prerequisites: Network access to the target's VNC port (5900) · Target running RealVNC 3.3.7
devstral-2 · analyzed Feb 16, 2026 Full analysis →

References (3)

Core 3
Core References
Third Party Advisory, VDB Entry vdb-entry x_refsource_xf
https://exchange.xforce.ibmcloud.com/vulnerabilities/6025
Patch, Vendor Advisory vdb-entry x_refsource_bid
http://www.securityfocus.com/bid/2305
Mailing List mailing-list x_refsource_bugtraq
http://marc.info/?l=bugtraq&m=98088315825366&w=2

Scores

EPSS 0.5081
EPSS Percentile 98.8%

Details

Status published
Products (1)
att/winvnc < 3.3.3r7
Published May 03, 2001
Tracked Since Feb 18, 2026