CVE-2021-20687Network attack vector

Administrator setting alteration via malicious page

Published Apr 7, 2021 · Updated Aug 3, 2024

Cross-site request forgery in daifukuya.com Kagemai 0.8.8 allows remote attackers to alter settings with administrator privileges. Kagemai processes a cross-site request under the logged-in administrator's session, but JVN does not identify the endpoint or missing request-validation control. Exploitation requires an administrator to view a malicious page while logged in, and the demonstrated consequence is unintended alteration of application settings.

CVSS severity4.3
Medium
EPSS probability0.56%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site request forgery in daifukuya.com Kagemai 0.8.8 allows remote attackers to alter settings with administrator privileges. Kagemai processes a cross-site request under the logged-in administrator's session, but JVN does not identify the endpoint or missing request-validation control. Exploitation requires an administrator to view a malicious page while logged in, and the demonstrated consequence is unintended alteration of application settings.

The record

CVE
CVE-2021-20687
Published
Apr 7, 2021
Updated
Aug 3, 2024
Vendor
daifukuya.com
Product
Kagemai
Classifications
CWE-352, T1204
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 7, 2021CVE 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=0.8.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

daifukuya.com · Kagemaiversion=0.8.8

Published CVSS scores

2.6JPCERT/CCAV:N/AC:H/Au:N/C:N/I:P/A:N
4.3JPCERT/CCCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

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-352Cross-Site Request Forgery (CSRF)
T1204User Execution

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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