Misskey up to 2026.3.0 improper authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability was found in Misskey up to 2026.3.0 and classified as critical. This impacts an unknown function. Executing a manipulation can lead to improper authorization. The identification of this vulnerability is CVE-2026-28431. The attack may be launched remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Misskey up to 2026.3.0. It has been declared as critical. This vulnerability affects an unknown code. The manipulation with an unknown input leads to a improper authorization vulnerability. The CWE definition for the vulnerability is CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality. CVE summarizes:

Misskey is an open source, federated social media platform. All Misskey servers running versions 8.45.0 and later, but prior to 2026.3.1, contain a vulnerability that allows bad actors access to data that they ordinarily wouldn't be able to access due to insufficient permission checks and proper input validation. This vulnerability occurs regardless of whether federation is enabled or not. This vulnerability could lead to a significant data breach. This vulnerability is fixed in 2026.3.1.

The advisory is shared for download at github.com. This vulnerability was named CVE-2026-28431 since 02/27/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1548.002.

Upgrading to version 2026.3.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CNNVD (CNNVD-202603-1959). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authorization
CWE: CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Misskey 2026.3.1

Timelineinfo

02/27/2026 CVE reserved
03/09/2026 +10 days Advisory disclosed
03/09/2026 +0 days VulDB entry created
03/13/2026 +4 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-28431 (🔒)
GCVE (CVE): GCVE-0-2026-28431
GCVE (VulDB): GCVE-100-349864
CNNVD: CNNVD-202603-1959 - Misskey 授权问题漏洞

Entryinfo

Created: 03/09/2026 23:24
Updated: 03/13/2026 18:52
Changes: 03/09/2026 23:24 (65), 03/11/2026 16:23 (6), 03/12/2026 23:55 (1), 03/13/2026 18:52 (11)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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