Misskey up to 2026.3.0 HTTP Signature Verification signature verification

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.2$0-$5k0.00

Summaryinfo

A vulnerability was found in Misskey up to 2026.3.0. It has been classified as problematic. Affected is an unknown function of the component HTTP Signature Verification. The manipulation leads to signature verification. This vulnerability is referenced as CVE-2026-28432. Remote exploitation of the attack is possible. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Misskey up to 2026.3.0. It has been rated as problematic. This issue affects an unknown code block of the component HTTP Signature Verification. The manipulation with an unknown input leads to a signature verification vulnerability. Using CWE to declare the problem leads to CWE-347. The product does not verify, or incorrectly verifies, the cryptographic signature for data. Impacted is integrity. The summary by CVE is:

Misskey is an open source, federated social media platform. All Misskey servers prior to 2026.3.1 contain a vulnerability that allows bypassing HTTP signature verification. Although this is a vulnerability related to federation, it affects all servers regardless of whether federation is enabled or disabled. This vulnerability is fixed in 2026.3.1.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-28432 since 02/27/2026. The exploitation is known to be difficult. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available.

Upgrading to version 2026.3.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CNNVD (CNNVD-202603-1960). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 3.1
VulDB Temp Score: 3.0
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: Signature verification
CWE: CWE-347 / CWE-345
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
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-2026-28432 (🔒)
GCVE (CVE): GCVE-0-2026-28432
GCVE (VulDB): GCVE-100-349865
CNNVD: CNNVD-202603-1960 - Misskey 数据伪造问题漏洞

Entryinfo

Created: 03/09/2026 23:24
Updated: 03/13/2026 18:52
Changes: 03/09/2026 23:24 (65), 03/11/2026 16:01 (6), 03/12/2026 23:55 (1), 03/13/2026 18:52 (11)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

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