Child pages
  • Legacy Security Levels
Skip to end of metadata
Go to start of metadata

Overview

This document explains the previous security levels of advisories that posted at http://www.cpanel.net/security. These security levels apply to Targeted Security Releases before TSR-2017-0002.

CVSSv2

For Targeted Security Releases from TSR-2015-0001 to TSR-2017-0001, we used the Common Vulnerability Scoring System version 2 (CVSSv2) to score vulnerabilities. When we disclosed a vulnerability, we provided the vulnerability's CVSSv2 Base Score and its Base Vector. You can use the CVSSv2 Base Vector to determine the complete CVSSv2 score.

Base Score and Base Metrics

The Base Score is a numeric value that ranges from 1 to 10, and increases as vulnerability levels increase. A value of 10 indicates the most severe vulnerabilities. The Base Metrics are vulnerability characteristics that remain constant regardless of changes in time or user environments.

To calculate the Base Score, assign values to the Base Metrics. For information about how to calculate base scores, visit first.org's A Complete Guide to the CVSSv2 documentation.

Base Vector

The Base Vector describes the components from which the Base Score is calculated. Base Vectors display in the following structure: 

(AV:[L,A,N]/AC:[H,M,L]/Au:[N,S,M]/C:[N,P,C]/I:[N,P,C]/A:[N,P,C])

You must choose one option for each set of brackets.

  • Metrics that the brackets do not contain are mandatory, and you must include them to create a valid CVSS vector.
  • Each letter or pair of letters represents a metric or metric value within CVSS.

The table below defines each Base Vector metric and their possible values:

MetricDescriptionPossible values
AVA vulnerability's network exploit level.
  • L — Local access
  • A — Adjacent network
  • N — Network
ACA vulnerability's required attack complexity.
  • H — High
  • M — Medium
  • L — Low
AuA vulnerability's required account authentication level.
  • N — None required
  • S — Requires single instance
  • M — Requires multiple instances
CA vulnerability's information confidentiality impact.
  • N — None
  • P — Partial
  • C — Complete
IA vulnerability's account integrity impact.
  • N — None
  • P — Partial
  • C — Complete
AA vulnerability's account availability impact.
  • N — None
  • P — Partial
  • C — Complete

For information about security levels prior to TSR-2015-0001, read the Legacy Security Levels documentation section below.

Legacy Security Levels

The following table lists the security levels in order of severity:

LevelDescription
CriticalA critical rating applies to vulnerabilities that allow remote, unauthenticated access and code execution, with no user interaction required. These vulnerabilities allow automated scripts such as worms to completely compromise the system.
Important

This rating applies to vulnerabilities that allow third parties to compromise system authentication levels

These vulnerabilities occur when you allow the following:

  • Local users to elevate their privilege levels.
  • Unauthenticated remote users to access resources that should require authentication to view.
  • Remote users to execute arbitrary code, which includes any local or remote attack that could result in an denial of service.
ModerateThis rating applies to vulnerabilities that rely on unlikely scenarios in order to compromise the system. These scenarios usually consist of a flawed or unlikely system configuration, and only occur in rare situations.
MinorThis rating applies to vulnerabilities that do not fit into the higher categories. These vulnerabilities occur in very unlikely situations and configurations, and they require extremely close timing of execution and events to occur that are out of the attacker's control. This rating also applies to vulnerabilities that, even if successful, result in few or no consequences on the system.

Additional documentation