Which products and versions are affected by CVE-2026-3891?

Affected: payment-gateway-pix-for-woocommerce (wordpress-plugin). The full list is in the CVE brief.

Is CVE-2026-3891 being exploited in the wild?

It is not listed in any known-exploited vulnerabilities catalog.

Is CVE-2026-3891 in the CISA KEV catalog?

No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.

Is there a public exploit for CVE-2026-3891?

Public exploit code is available.

Is there a fix for CVE-2026-3891?

Fixed versions are available, including payment-gateway-pix-for-woocommerce 1.6.0.

How urgently should CVE-2026-3891 be patched?

Brandefense priority: patch immediately, because public exploit code exists for a high-severity flaw.

Request A Demo

Vulnerability Intelligence

CVE-2026-3891

Q: What is CVE-2026-3891?

The Pix for WooCommerce plugin for WordPress is vulnerable to arbitrary file uploads due to missing capability check and missing file type validation in the 'lkn_pix_for_woocommerce_c6_save_settings' function in all versions up to, and including, 1.5.0.

CriticalPublic exploit

Pix for WooCommerce <= 1.5.0 - Unauthenticated Arbitrary File Upload

Published Mar 13, 2026 · Updated Apr 8, 2026 · Also known as 20188fd3-c330-4c76-912b-72731e14c450

Key Facts

Patch immediately

CVE-2026-3891 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting payment-gateway-pix-for-woocommerce (wordpress-plugin).
It is not listed in any known-exploited vulnerabilities catalog. Public exploit code is available.
EPSS estimates a 30% probability of exploitation in the next 30 days.
Fixed versions are available, including payment-gateway-pix-for-woocommerce 1.6.0.
Brandefense priority: patch immediately, because public exploit code exists for a high-severity flaw.

CVSS v3.1

9.8

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS (30-day exploit likelihood)

30%

Higher than 98.1% of all scored CVEs

Exploited in the wild

No known

Not in a known-exploited catalog

Public exploit code

Available

Proof-of-concept or weaponized module

Get the full CVE-2026-3891 brief as a PDF

Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.

Description

The Pix for WooCommerce plugin for WordPress is vulnerable to arbitrary file uploads due to missing capability check and missing file type validation in the 'lkn_pix_for_woocommerce_c6_save_settings' function in all versions up to, and including, 1.5.0. This makes it possible for unauthenticated attackers to upload arbitrary files on the affected site's server which may make remote code execution possible.

Affected Products

2 affected entries in total

Product	Affected versions	Fixed in
payment-gateway-pix-for-woocommercewordpress-plugin	See advisory	1.6.0

Patched Releases

payment-gateway-pix-for-woocommerce

1.6.0

Timeline

Publicly disclosed
Mar 13, 2026
Last updated
Apr 8, 2026

Weakness Type

CWE-434 Unrestricted Upload of File with Dangerous Type

References

2 more references in the full CVE brief

FAQ

Common Questions.

The Pix for WooCommerce plugin for WordPress is vulnerable to arbitrary file uploads due to missing capability check and missing file type validation in the 'lkn_pix_for_woocommerce_c6_save_settings' function in all versions up to, and including, 1.5.0.
Affected: payment-gateway-pix-for-woocommerce (wordpress-plugin). The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
Fixed versions are available, including payment-gateway-pix-for-woocommerce 1.6.0.
Brandefense priority: patch immediately, because public exploit code exists for a high-severity flaw.

Is CVE-2026-3891 Running On Your Attack Surface?

Brandefense maps vulnerabilities like this one to your internet-facing assets and tells you exactly where to patch.

Request A Demo