CVE-2021-24161Network attack vector

Remote code execution via nonce-free theme import

Published Apr 5, 2021 · Updated Aug 3, 2024

CSRF in ExpressTech Systems Responsive Menu and Responsive Menu Pro before 4.0.4 allows remote attackers to execute PHP code. The legacy theme-import handler accepts the responsive-menu-import-theme POST flag and extracts the supplied ZIP into a public uploads directory without verifying a WordPress nonce. Exploitation requires an authenticated administrator to submit the forged request; attacker-supplied PHP can then be requested from the site to run code.

CVSS severity8.8
High
EPSS probability1.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

CSRF in ExpressTech Systems Responsive Menu and Responsive Menu Pro before 4.0.4 allows remote attackers to execute PHP code. The legacy theme-import handler accepts the responsive-menu-import-theme POST flag and extracts the supplied ZIP into a public uploads directory without verifying a WordPress nonce. Exploitation requires an authenticated administrator to submit the forged request; attacker-supplied PHP can then be requested from the site to run code.

The record

CVE
CVE-2021-24161
Published
Apr 5, 2021
Updated
Aug 3, 2024
Vendor
ExpressTech Systems
Product
Responsive Menu
Classifications
CWE-352, T1204.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 5, 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=4.0.4 <4.0.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ExpressTech Systems · Responsive Menuversion=4.0.4 <4.0.4
ExpressTech Systems · Responsive Menu Proversion=4.0.4 <4.0.4

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NIST NVDAV:N/AC:M/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-352Cross-Site Request Forgery (CSRF)
T1204.001Malicious Link

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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