CVE-2020-5561Network attack vector

Unauthenticated remote OS command execution

Published Mar 25, 2020 · Updated Aug 4, 2024

OS command injection in Mash room - Free CGI - Keijiban Tsumiki 1.15 allows remote attackers to execute commands on the server. JPCERT/CC and IPA confirmed command execution in the server-side CGI application, but the affected parameter and unsafe command-building operation are undisclosed. No authentication or user interaction is required; injected commands run with the web application's server-side privileges and can read, alter, or interrupt hosted data and services.

CVSS severity7.3
High
EPSS probability2.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

OS command injection in Mash room - Free CGI - Keijiban Tsumiki 1.15 allows remote attackers to execute commands on the server. JPCERT/CC and IPA confirmed command execution in the server-side CGI application, but the affected parameter and unsafe command-building operation are undisclosed. No authentication or user interaction is required; injected commands run with the web application's server-side privileges and can read, alter, or interrupt hosted data and services.

The record

CVE
CVE-2020-5561
Published
Mar 25, 2020
Updated
Aug 4, 2024
Vendor
Mash room - Free CGI -
Product
Keijiban Tsumiki
Classifications
CWE-78, T1059
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 25, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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=v1.15

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mash room - Free CGI - · Keijiban Tsumikiversion=v1.15

Published CVSS scores

7.3JPCERT/CCCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
7.5JPCERT/CCAV: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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1059Command and Scripting Interpreter

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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