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VNC No Authentication Detection

vnc-no-auth is a critical severity check in the network category, written in c. Its source is templates/network/vnc/vnc-no-auth.c in cert-x-gen-templates.

Detects VNC servers allowing connections without authentication using RFB protocol handshake

Field Value
Id vnc-no-auth
Severity critical
Language c
Category network
Author CERT-X-GEN Security Team
Template version 1.0.0
Confidence 100
CVSS 9.8
Weakness CWE-306
Tags vnc, remote-access, no-auth, binary-protocol, rce
Target kind not recorded
Oracle not recorded

Declared in the header. cxg parses @references and then discards it, and nothing at scan time reads it, so this is the only place the links a template cites are surfaced.

To see what the copy on your machine says about itself, and to confirm it is installed at all:

Terminal window
cxg template info vnc-no-auth

The id it prints is the one to pass anywhere a template is selected. See cxg template for the rest of the subcommand, Scan a target for running a scan, and A match is not a finding for how to read what comes back.