CVE-2021-47937Public exploitNetwork attack vectorHinoki check available

Authenticated command execution via malicious theme upload

Published May 10, 2026 · Updated May 10, 2026

Remote code execution in e107 CMS 2.3.0 allows remote authenticated users to execute system commands through a malicious theme upload. The theme.php endpoint accepts a crafted ZIP containing executable PHP and extracts its payload into the web-accessible e107_themes directory. Theme-installation permission is required; the uploaded payload.php web shell then runs attacker-supplied commands with the web server process's authority.

CVSS severity8.7
High
EPSS probability0.59%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Remote code execution in e107 CMS 2.3.0 allows remote authenticated users to execute system commands through a malicious theme upload. The theme.php endpoint accepts a crafted ZIP containing executable PHP and extracts its payload into the web-accessible e107_themes directory. Theme-installation permission is required; the uploaded payload.php web shell then runs attacker-supplied commands with the web server process's authority.

The record

CVE
CVE-2021-47937
Published
May 10, 2026
Updated
May 10, 2026
Vendor
e107
Product
e107
Classifications
CWE-434, T1505.003
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 10, 2026CVE publishedPublication date reported by the CVE source.
  2. May 10, 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=2.3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

e107 · e107version=2.3.0

Published CVSS scores

8.7VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA: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.

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-434Unrestricted Upload of File with Dangerous Type
T1505.003Web 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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