CVE-2026-3891Public exploitNetwork attack vector

Unauthenticated code execution via unchecked certificate upload

Published Mar 13, 2026 · Updated Mar 13, 2026

Arbitrary file upload in Pix for WooCommerce 1.5.0 and earlier allows remote attackers to place executable files on WordPress servers. The lkn_pix_for_woocommerce_c6_save_settings AJAX handler omits capability and file-type checks, while a public nonce endpoint supplies the token needed to submit an upload. No account or user interaction is required; a PHP file stored beneath the plugin's web-accessible directory executes with web-server privileges.

CVSS severity9.8
Critical
EPSS probability25.06%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Arbitrary file upload in Pix for WooCommerce 1.5.0 and earlier allows remote attackers to place executable files on WordPress servers. The lkn_pix_for_woocommerce_c6_save_settings AJAX handler omits capability and file-type checks, while a public nonce endpoint supplies the token needed to submit an upload. No account or user interaction is required; a PHP file stored beneath the plugin's web-accessible directory executes with web-server privileges.

The record

CVE
CVE-2026-3891
Published
Mar 13, 2026
Updated
Mar 13, 2026
Vendor
Link Nacional
Product
Pix for WooCommerce
Classifications
CWE-434, T1505.003, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 13, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 13, 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=* <=1.5.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Link Nacional · Pix for WooCommerceversion=* <=1.5.0

Published CVSS scores

9.8WordfenceCVSS: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 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 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.

Technologies

Your stack

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Your stack

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