What is the CVSS score of CVE-2020-29454?

CVE-2020-29454 has a CVSS 3.1 base score of 4.3 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N. EPSS exploitation probability: 0.9%.

Is there a patch available for CVE-2020-29454?

Yes, a patch is available for CVE-2020-29454. Update the affected software to the latest version immediately.

Umbraco CVE-2020-29454

MEDIUM

Incorrect Authorization (CWE-863)

2020-12-02 cve@mitre.org

Authentication Bypass Umbraco Cms Umbraco

4.3

CVSS 3.1 · NVD

View

Vulnerability Assessment

Weakness	CWE CWE-863 OWASP Top 10:2025 A01:2025 - Broken Access Control ASVS 5.0 V8 - Authorization Authorization logic validation MITRE ATT&CK 1 technique across 1 tactic: Privilege Escalation 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 4.3 (MEDIUM). Attack characteristics: network attack vector, low complexity, low privileges required, no user interaction not required.
Exploit ScenarioDerived	A remote attacker could bypass authorization checks to access restricted resources by sending crafted requests to the affected application.

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

Patch available 0.9% exploitation probability (EPSS)

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

Alert me

AnalysisAI

Editors/LogViewerController.cs in Umbraco through 8.9.1 allows a user to visit a logviewer endpoint even if they lack Applications.Settings access. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Review and test authorization logic, implement consistent access control checks, use centralized authorization framework.

Affected Packages

nuget umbracocms fix: 8.10.0

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 1 package in nuget

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 Incorrect Authorization (CWE-863), which allows attackers to bypass authorization checks to access restricted resources. Editors/LogViewerController.cs in Umbraco through 8.9.1 allows a user to visit a logviewer endpoint even if they lack Applications.Settings access. Affected products include: Umbraco Umbraco Cms. Version information: through 8.9.1.

Know when Umbraco 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 4.3 MEDIUM

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

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

None

DescriptionNVD

Editors/LogViewerController.cs in Umbraco through 8.9.1 allows a user to visit a logviewer endpoint even if they lack Applications.Settings access.

Threat Intelligence Overview

EPSS Score

0.9%

Top 45% exploitable

Data Quality

3 sources

Confidence: Low

NVD

CVE.org

EPSS

GitHub

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 0.9%

Patch available Yes

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: +22

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:umbraco:umbraco_cms:*:*:*:*:*:*:*:*

More in Umbraco

View all

CVE-2012-10054 CRITICAL Act Now POC

9.3 Aug 13

Umbraco CMS versions prior to 4.7.1 are vulnerable to unauthenticated remote code execution via the codeEditorSave.asmx

CVE-2015-8813 HIGH Act Now POC

8.2 Mar 03

The Page_Load function in Umbraco.Web/umbraco.presentation/umbraco/dashboard/FeedProxy.aspx.cs in Umbraco before 7.4.0 a

CVE-2020-9471 HIGH This Week POC

8.8 Mar 16

Umbraco Cloud 8.5.3 allows an authenticated file upload (and consequently Remote Code Execution) via the Install Package

CVE-2021-47776 MEDIUM This Month POC

6.9 Jan 15

Umbraco CMS v8.14.1 contains a server-side request forgery vulnerability that allows attackers to manipulate baseUrl par

CVE-2024-10761 MEDIUM This Month POC

6.9 Nov 04

A vulnerability was found in Umbraco CMS up to 10.7.7/12.3.6/13.5.2/14.3.1/15.1.1. Rated medium severity (CVSS 6.9), thi

CVE-2024-55488 MEDIUM This Month POC

6.5 Jan 22

A stored cross-site scripting (XSS) vulnerability in Umbraco CMS v14.3.1 allows attackers to execute arbitrary web scrip

CVE-2020-5811 MEDIUM This Month POC

6.5 Dec 30

An authenticated path traversal vulnerability exists during package installation in Umbraco CMS <= 8.9.1 or current, whi

CVE-2020-9472 MEDIUM This Month POC

6.5 Mar 16

Umbraco CMS 8.5.3 allows an authenticated file upload (and consequently Remote Code Execution) via the Install Package f

CVE-2012-1301 CRITICAL Act Now

9.8 Apr 13

The FeedProxy.aspx script in Umbraco 4.7.0 allows remote attackers to proxy requests on their behalf via the "url" param

CVE-2015-8815 MEDIUM This Month POC

6.1 Mar 03

Multiple cross-site scripting (XSS) vulnerabilities in Umbraco before 7.4.0 allow remote attackers to inject arbitrary w

CVE-2025-67288 CRITICAL Act Now

10.0 Dec 22

Arbitrary code execution in Umbraco CMS 16.3.3 is claimed via upload of a crafted PDF file that abuses insufficient file

CVE-2021-33224 CRITICAL Act Now

9.8 Feb 24

File upload vulnerability in Umbraco Forms v.8.7.0 allows unauthenticated attackers to execute arbitrary code via a craf

Same weakness CWE-863 – Incorrect Authorization

View all

CVE-2025-54253 CRITICAL POC

10.0

CVE-2025-24200 MEDIUM

6.1

CVE-2026-71362 CRITICAL POC

9.1

CVE-2026-42016 HIGH POC

8.8

CVE-2023-21715 HIGH

7.3

CVE-2025-21480 HIGH

8.6

CVE-2025-21479 HIGH

8.6

CVE-2025-32462 HIGH POC

8.8

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-2022-40684 CRITICAL POC

9.8

CVE-2025-61882 CRITICAL POC

9.8

CVE-2024-0012 CRITICAL POC

9.3

References

Advisories & patches

REF https://github.com/umbraco/Umbraco-CMS/pull/9361

Search Externally

GitHub PoC

Exploit-DB PacketStorm Snyk Rapid7 Nuclei Templates Trickest PoC

Back