What is the CVSS score of CVE-2020-14455?

CVE-2020-14455 has a CVSS 3.1 base score of 6.5 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N. EPSS exploitation probability: 1.2%.

Mattermost CVE-2020-14455

MEDIUM

Improper Authentication (CWE-287)

2020-06-19 cve@mitre.org

Authentication Bypass Mattermost Mattermost Desktop

6.5

CVSS 3.1 · NVD

View

Vulnerability Assessment

Weakness	CWE CWE-287 OWASP Top 10:2025 A07:2025 - Authentication Failures ASVS 5.0 V6 - Authentication Authentication mechanism validation MITRE ATT&CK 2 techniques across 2 tactics: Defense Evasion, Initial Access The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. Sign in to read
Impact	CVSS score of 6.5 (MEDIUM). Attack characteristics: network attack vector, low complexity, no privileges required, user interaction required.
Exploit ScenarioDerived	A remote attacker could bypass authentication mechanisms to gain unauthorized access by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability.

This Month Plan within 30 days. Why: MEDIUM severity (CVSS 4.0-6.9).

No patch listed yet 1.2% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAI

An issue was discovered in Mattermost Desktop App before 4.4.0. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Implement multi-factor authentication, enforce strong password policies, use proven authentication frameworks.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

This vulnerability is classified as Improper Authentication (CWE-287), which allows attackers to bypass authentication mechanisms to gain unauthorized access. An issue was discovered in Mattermost Desktop App before 4.4.0. Prompting for HTTP Basic Authentication is mishandled, allowing phishing, aka MMSA-2020-0007. Affected products include: Mattermost Mattermost Desktop. Version information: before 4.4.0..

Know when Mattermost gets its next vulnerability

Watch products and get an email when something new is published
Check this CVE against your own stack and servers
Exploit and PoC references, threat intelligence from 22 sources

Continue with Google Continue with GitHub

No credit card · 7-day full trial

Severity by source

NVD PRIMARY 6.5 MEDIUM

AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

DescriptionNVD

An issue was discovered in Mattermost Desktop App before 4.4.0. Prompting for HTTP Basic Authentication is mishandled, allowing phishing, aka MMSA-2020-0007.

Threat Intelligence Overview

EPSS Score

1.2%

Top 36% exploitable

Data Quality

2 sources

Confidence: Low

NVD

CVE.org

EPSS

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue

Severity MEDIUM

CISA KEV No

Public POC No

EPSS 1.2%

Patch available No

Active threat No

Deciding rule

MEDIUM severity (CVSS 4.0-6.9)

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived

Scheduled

Exploitation· derived

None

System Exposure· derived

Open

Automatable· derived

Human Impact· derived

Medium

Priority Score

Low Medium High Critical

KEV: 0

EPSS: +1

CVSS: +32

PoC: 0

Weaponized: 0

Threat intel: 0

Gov advisory: 0

Attack Technique

Authentication Bypass CRITICAL

Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.

Affected Products (CPE)NVD

cpe:2.3:a:mattermost:mattermost_desktop:*:*:*:*:*:*:*:*

More in Mattermost

View all

CVE-2025-25279 CRITICAL Act Now

9.9 Feb 24

Mattermost versions 10.4.x <= 10.4.1, 9.11.x <= 9.11.7, 10.3.x <= 10.3.2, 10.2.x <= 10.2.2 fail to properly validate boa

CVE-2026-48801 HIGH This Week POC

8.7 Jun 26

Denial of service in linkify-it (npm) through v5.0.0 lets remote unauthenticated attackers wedge a rendering worker by s

CVE-2022-4044 MEDIUM This Month POC

6.5 Nov 23

A denial-of-service vulnerability in Mattermost allows an authenticated user to crash the server via multiple large auto

CVE-2022-3257 MEDIUM This Month POC

6.5 Sep 23

Mattermost version 7.1.x and earlier fails to sufficiently process a specifically crafted GIF file when it is uploaded w

CVE-2025-4981 CRITICAL Act Now

9.9 Jun 20

A remote code execution vulnerability (CVSS 9.9) that allows authenticated users. Critical severity with potential for s

CVE-2025-20051 CRITICAL Act Now

9.9 Feb 24

Mattermost versions 10.4.x <= 10.4.1, 9.11.x <= 9.11.7, 10.3.x <= 10.3.2, 10.2.x <= 10.2.2 fail to properly validate inp

CVE-2026-4858 CRITICAL Act Now

9.9 May 21

Privilege escalation to full administrative control in Mattermost self-hosted server (versions 11.6.0 and earlier in the

CVE-2025-12421 CRITICAL Act Now

9.9 Nov 27

Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to to verify that t

CVE-2025-12419 CRITICAL Act Now

9.9 Nov 27

Mattermost versions 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12, 11.0.x <= 11.0.3 fail to properly validat

CVE-2023-6458 CRITICAL Act Now

9.8 Dec 06

Mattermost webapp fails to validate route parameters in/<TEAM_NAME>/channels/<CHANNEL_NAME> allowing an attacker to perf

CVE-2020-26276 CRITICAL Act Now

9.8 Dec 17

Fleet is an open source osquery manager. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable,

CVE-2025-24490 CRITICAL Act Now

9.6 Feb 24

Mattermost versions 10.4.x <= 10.4.1, 9.11.x <= 9.11.7, 10.3.x <= 10.3.2, 10.2.x <= 10.2.2 fail to use prepared statemen

Same weakness CWE-287 – Improper Authentication

View all

CVE-2022-40684 CRITICAL POC

9.8

CVE-2025-61882 CRITICAL POC

9.8

CVE-2020-0688 HIGH POC

8.8

CVE-2023-46805 HIGH POC

8.2

CVE-2023-35078 CRITICAL POC

9.8

CVE-2015-1187 CRITICAL POC

9.8

CVE-2024-7593 CRITICAL POC

9.8

CVE-2017-7921 CRITICAL POC

9.8

Same technique Authentication Bypass

View all

CVE-2015-3306 CRITICAL POC

10.0

CVE-2023-22515 CRITICAL POC

9.8

CVE-2012-4681 CRITICAL POC

9.8

CVE-2013-2465 CRITICAL POC

9.8

CVE-2011-3544 CRITICAL POC

9.8

CVE-2024-0012 CRITICAL POC

9.3

References

Advisories & patches

ADVISORY https://mattermost.com/security-updates/

Search Externally

GitHub PoC

Exploit-DB PacketStorm Snyk Rapid7 Nuclei Templates Trickest PoC

Back