CVE-2021-24212Known exploitationPublic exploitNetwork attack vector

Remote code execution via unrestricted attachment upload

Published Apr 5, 2021 · Updated Aug 3, 2024

Unrestricted file upload in OPMC Help Scout Integration for WooCommerce before 2.9.1 allows remote attackers to execute PHP code. The WC_Help_Scout_Ajax::wc_help_scout_upload_attachments handler moves an unauthenticated multipart upload into wp-content/uploads/hstmp under its supplied filename. On deployments that execute PHP from the uploads tree, no account is required to run the payload with the web server's privileges.

CVSS severity9.8
Critical
EPSS probability7.91%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Unrestricted file upload in OPMC Help Scout Integration for WooCommerce before 2.9.1 allows remote attackers to execute PHP code. The WC_Help_Scout_Ajax::wc_help_scout_upload_attachments handler moves an unauthenticated multipart upload into wp-content/uploads/hstmp under its supplied filename. On deployments that execute PHP from the uploads tree, no account is required to run the payload with the web server's privileges.

The record

CVE
CVE-2021-24212
Published
Apr 5, 2021
Updated
Aug 3, 2024
Vendor
OPMC
Product
Help Scout Integration for WooCommerce
Classifications
CWE-434, T1505.003, T1190
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=2.9.1 <2.9.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

OPMC · Help Scout Integration for WooCommerceversion=2.9.1 <2.9.1

Published CVSS scores

7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/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
Privilegesunauthenticated
Known exploitationReported
Public exploitPublished

Weakness, pattern, technique

CWE-434Unrestricted Upload of File with Dangerous Type
T1505.003Web Shell
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Reported exploitation

Technologies

Your stack

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Your stack

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