HighPublic exploit

Buffer Overflow in AT&T WinVNC Client 3.3.3r7 and earlier

IdentifiersCVE-2001-0167CWE-120

A buffer overflow vulnerability exists in AT&T WinVNC (Virtual Network Computing) client versions 3.3.3r7 and earlier. The vulnerability is triggered when the client receives a specially crafted rfbConnFailed packet containing an excessively long reason string, which overflows a buffer and allows for the execution of arbitrary code.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation allows a remote attacker to execute arbitrary commands on the system running the vulnerable WinVNC client, potentially leading to full system compromise with the privileges of the user running the client.

Mitigation

If you can’t patch tonight, do this now.

Avoid connecting to untrusted or unknown VNC servers. Employ network-level protections such as firewalls to restrict VNC client connections to trusted servers only. Consider using application whitelisting and endpoint protection to reduce the risk of exploitation.

Remediation

Patch, then assume compromise.

Upgrade to a version of WinVNC client later than 3.3.3r7 in which this buffer overflow vulnerability has been patched. Ensure that all VNC client software is kept up to date with the latest security patches.

PUBLIC EXPLOITS

Exploits

1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos.

VALID 1 / 1 TOTALView more in app

realvnc_client.rbMaturityWeaponizedFrameworkmetasploitVerified exploit

This repository contains a single Metasploit exploit module targeting a buffer overflow vulnerability in RealVNC 3.3.7's vncviewer.exe (CVE-2001-0167). The exploit works by running a fake VNC server (default port 5900) and waiting for a vulnerable client to connect. Upon connection, the module sends a specially crafted response that overflows a buffer in the client, allowing arbitrary code execution. The payload is customizable using Metasploit's payload system and is encoded to avoid problematic characters. The exploit targets Windows 2000 SP4, Windows XP SP2, and Windows 2003 SP1 (all English versions). The repository is structured as a single Ruby file compatible with the Metasploit framework, and its primary purpose is to provide a remote code execution exploit for penetration testers and security researchers.

Disclosed Jan 29, 2001rubynetwork

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType

AttWinvncapplication

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

ACTIVITY FEED

Recent activity

No public activity tracked yet. Mallory keeps watching.

0 SOURCESView more in app

No public activity observed for this vulnerability.

What this page doesn’t show

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Exposure mapping

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Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity