CVE-2021-47736Public exploitNetwork attack vector

Authenticated code execution via content-file PHP injection

Published Dec 23, 2025 · Updated Jul 15, 2026

Code injection in CMSimple_XH 1.7.4 allows remote authenticated users to execute arbitrary commands through content editing. The content save action accepts a valid CSRF token and writes attacker-supplied PHP into the web-served content file, which then creates a command-executing PHP shell. Administrative credentials are required, and commands run with the web server process's permissions.

CVSS severity8.6
High
EPSS probability1.05%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Code injection in CMSimple_XH 1.7.4 allows remote authenticated users to execute arbitrary commands through content editing. The content save action accepts a valid CSRF token and writes attacker-supplied PHP into the web-served content file, which then creates a command-executing PHP shell. Administrative credentials are required, and commands run with the web server process's permissions.

The record

CVE
CVE-2021-47736
Published
Dec 23, 2025
Updated
Jul 15, 2026
Vendor
CMSimple_XH
Product
CMSimple_XH
Classifications
CWE-94, T1505.003
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Dec 23, 2025CVE publishedPublication date reported by the CVE source.
  2. Jul 15, 2026Record 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=1.7.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

CMSimple_XH · CMSimple_XHversion=1.7.4

Published CVSS scores

8.6VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
7.2VulnCheckCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-94Improper Control of Generation of Code ('Code Injection')
T1505.003Server Software Component: Web Shell

Public exploit references

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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