SSL Certificate Null Character Spoofing Weakness

high Nessus Plugin ID 42053

Synopsis

This plugin determines if the remote SSL certificate contains a Null character.

Description

The remote host contains an SSL certificate with a common name containing a Null character (\x00) in it. This may indicate a compromise or that a program such as SSLsniff is spoofing the certificate in order to intercept the traffic via a Man-in-The-Middle (MiTM) attack.

Certificates with such characters may exploit a bug contained in many different web browser and other SSL-related products, in how they validate the common name of such a certificate.

Solution

Recreate the remote SSL certificate.

See Also

https://moxie.org/papers/null-prefix-attacks.pdf

Plugin Details

Severity: High

ID: 42053

File Name: ssl_null_byte_in_cn.nasl

Version: 1.12

Type: remote

Family: General

Published: 10/6/2009

Updated: 10/26/2020

Supported Sensors: Nessus

Risk Information

CVSS v2

Risk Factor: High

Base Score: 8.3

Vector: CVSS2#AV:A/AC:L/Au:N/C:C/I:C/A:C

Vulnerability Information

Required KB Items: SSL/Supported