What is the CVSS score of CVE-2021-43858?

CVE-2021-43858 has a CVSS 3.1 base score of 8.8 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 35.5%.

Is there a patch available for CVE-2021-43858?

Yes, a patch is available for CVE-2021-43858. Update the affected software to the latest version immediately.

Minio CVE-2021-43858

HIGH

Improper Privilege Management (CWE-269)

2021-12-27 security-advisories@github.com

Privilege Escalation Kubernetes Minio

8.8

CVSS 3.1 · Vendor: github

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Vulnerability Assessment

Weakness	CWE CWE-269 OWASP Top 10:2025 A06:2025 - Insecure Design ASVS 5.0 V8 - Authorization Least privilege enforcement 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 8.8 (HIGH). Attack characteristics: network attack vector, low complexity, low privileges required, no user interaction not required.
Exploit ScenarioDerived	A remote attacker could escalate privileges to gain unauthorized elevated access by sending crafted requests to the affected application.

This Week Schedule remediation this week. Why: HIGH severity + EPSS > 10%.

Patch available 35.5% exploitation probability (EPSS)

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AnalysisAI

MinIO is a Kubernetes native application for cloud storage. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. This Improper Privilege Management vulnerability could allow attackers to escalate privileges to gain unauthorized elevated access.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply principle of least privilege, validate privilege transitions, implement proper role separation.

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 Privilege Management (CWE-269), which allows attackers to escalate privileges to gain unauthorized elevated access. MinIO is a Kubernetes native application for cloud storage. Prior to version RELEASE.2021-12-27T07-23-18Z, a malicious client can hand-craft an HTTP API call that allows for updating policy for a user and gaining higher privileges. The patch in version RELEASE.2021-12-27T07-23-18Z changes the accepted request body type and removes the ability to apply policy changes through this API. There is a workaround for this vulnerability: Changing passwords can be disabled by adding an explicit Deny rule to disable the API for users. Affected products include: Minio.

Severity by source

Vendor (github) PRIMARY 8.8 HIGH

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

Primary rating from Vendor (github) · only source for this CVE.

CVSS VectorVendor: github

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

DescriptionCVE.org

MinIO is a Kubernetes native application for cloud storage. Prior to version RELEASE.2021-12-27T07-23-18Z, a malicious client can hand-craft an HTTP API call that allows for updating policy for a user and gaining higher privileges. The patch in version RELEASE.2021-12-27T07-23-18Z changes the accepted request body type and removes the ability to apply policy changes through this API. There is a workaround for this vulnerability: Changing passwords can be disabled by adding an explicit Deny rule to disable the API for users.

Threat Intelligence Overview

EPSS Score

35.5%

Top 2% 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 HIGH

CISA KEV No

Public POC No

EPSS 35.5%

Patch available Yes

Active threat No

Deciding rule

HIGH severity + EPSS > 10%

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: +35

CVSS: +44

PoC: 0

Weaponized: 0

Threat intel: 0

Gov advisory: 0

Attack Technique

Privilege Escalation HIGH

Privilege escalation occurs when an attacker leverages flaws in access control mechanisms to gain permissions beyond what they were originally granted.