What is the CVSS score of CVE-2021-20737?

CVE-2021-20737 has a CVSS 3.1 base score of 6.5 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N. EPSS exploitation probability: 1.1%.

Growi CVE-2021-20737

MEDIUM

Improper Authentication (CWE-287)

2021-06-22 vultures@jpcert.or.jp

Authentication Bypass Growi Weseek

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, low privileges required, no user interaction not required.
Exploit ScenarioDerived	A remote attacker could bypass authentication mechanisms to gain unauthorized access by sending crafted requests to the affected application.

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

No patch listed yet 1.1% exploitation probability (EPSS)

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

Alert me

AnalysisAI

Improper authentication vulnerability in GROWI versions prior to v4.2.20 allows a remote attacker to view the unauthorized pages without access privileges via unspecified vectors. Rated medium severity (CVSS 6.5), 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. 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. Improper authentication vulnerability in GROWI versions prior to v4.2.20 allows a remote attacker to view the unauthorized pages without access privileges via unspecified vectors. Affected products include: Weseek Growi.

Know when Growi 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:L/UI:N/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

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

DescriptionNVD

Improper authentication vulnerability in GROWI versions prior to v4.2.20 allows a remote attacker to view the unauthorized pages without access privileges via unspecified vectors.

Threat Intelligence Overview

EPSS Score

1.1%

Top 40% 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 1.1%

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:weseek:growi:*:*:*:*:*:*:*:*

More in Growi

View all

CVE-2021-20736 CRITICAL Act Now

9.1 Jun 22

NoSQL injection vulnerability in GROWI versions prior to v4.2.20 allows a remote attacker to obtain and/or alter the inf

CVE-2019-5968 HIGH This Week

8.8 Jul 05

Cross-site request forgery (CSRF) vulnerability in GROWI v3.4.6 and earlier allows remote attackers to hijack the authen

CVE-2026-80191 HIGH This Week

8.7 Aug 25

Unauthenticated file disclosure in GROWI (all versions before 8.0.2) exposes private page attachments to any caller who

CVE-2026-41040 HIGH This Week

8.7 Apr 23

Remote denial of service via regular expression attack in GROWI allows unauthenticated network attackers to exhaust serv

CVE-2026-25083 HIGH This Week

8.7 Mar 16

Cross-user data exposure and tampering in GROWI v7.4.5 and earlier allows any authenticated user who learns a shared AI

CVE-2026-41951 HIGH This Week

8.6 May 11

Remote path traversal in GROWI v7.5.0 and earlier allows authenticated administrators to execute arbitrary EJS templates

CVE-2021-20670 HIGH This Week

7.5 Mar 10

Improper access control vulnerability in GROWI versions v4.2.2 and earlier allows a remote unauthenticated attacker to r

CVE-2020-5683 HIGH This Week

7.5 Dec 16

Directory traversal vulnerability in GROWI versions prior to v4.2.3 (v4.2 Series), GROWI versions prior to v4.1.12 (v4.1

CVE-2020-5682 HIGH This Week

7.5 Dec 16

Improper input validation in GROWI versions prior to v4.2.3 (v4.2 Series), GROWI versions prior to v4.1.12 (v4.1 Series)

CVE-2020-5676 HIGH This Week

7.5 Dec 03

GROWI v4.1.3 and earlier allow remote attackers to obtain information which is not allowed to access via unspecified vec

CVE-2019-13338 HIGH This Week

7.5 Jul 09

In WESEEK GROWI before 3.5.0, a remote attacker can obtain the password hash of the creator of a page by leveraging wiki

CVE-2019-13337 HIGH This Week

7.5 Jul 09

In WESEEK GROWI before 3.5.0, the site-wide basic authentication can be bypassed by adding a URL parameter access_token

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://weseek.co.jp/security/2021/06/14/vulnerability/growi-nosql-ingection/ REF https://jvn.jp/en/jp/JVN95457785/index.html

Search Externally

GitHub PoC

Exploit-DB PacketStorm Snyk Rapid7 Nuclei Templates Trickest PoC

Back