CVE-2021-26634Network attack vector

Unauthenticated code execution via unchecked inputs and uploads

Published Jun 1, 2022 · Updated Aug 3, 2024

SQL injection and unrestricted file upload in Max Yi MaxBoard 1.9.5.1 and earlier allow remote attackers to execute arbitrary code. Unspecified parameters and variables fail to validate input values and file extensions, enabling database injection and web-shell upload. No authentication or user interaction is required, and successful exploitation can grant server-management privileges.

CVSS severity9.8
Critical
EPSS probability1.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

SQL injection and unrestricted file upload in Max Yi MaxBoard 1.9.5.1 and earlier allow remote attackers to execute arbitrary code. Unspecified parameters and variables fail to validate input values and file extensions, enabling database injection and web-shell upload. No authentication or user interaction is required, and successful exploitation can grant server-management privileges.

The record

CVE
CVE-2021-26634
Published
Jun 1, 2022
Updated
Aug 3, 2024
Vendor
Max Yi
Product
MaxBoard
Classifications
CWE-434, CWE-288, CWE-89, T1190, T1505.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 1, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <=1.9.5.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Max Yi · MaxBoardversion=unspecified <=1.9.5.1

Published CVSS scores

9.8KrCERT/CCCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NVDAV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-434Unrestricted Upload of File with Dangerous Type
CWE-288Authentication Bypass Using an Alternate Path or Channel
CWE-89Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
T1190Exploit Public-Facing Application
T1505.003Web Shell

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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