CVE-2026-3891 Details.
Pix for WooCommerce <= 1.5.0 - Unauthenticated Arbitrary File Upload
Atlas does not check this one. Needs requests that change data.
To test for this one, the check would have to send requests that could change data on the site. Atlas only ever reads public pages, so it does not run this check.
About CVE-2026-3891. What It Means.
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 Product. What Is Hit.
- Vendor
- linknacional
- Product
- Linknacional Payment Gateway Pix For WooCommerce
FAQ
Common Questions.
Pix for WooCommerce <= 1.5.0 - Unauthenticated Arbitrary File Upload. 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.
No. To test for this one, the check would have to send requests that could change data on the site. Atlas only ever reads public pages, so it does not run this check. The facts about CVE-2026-3891 are on this page, and you can request a demo to see how Brandefense watches your whole external attack surface.
CVE-2026-3891 is not on the CISA Known Exploited Vulnerabilities list at the time of writing, but it is still worth fixing.
Update Linknacional Payment Gateway Pix For WooCommerce to the latest version from the vendor, or follow the vendor's advice to switch off the affected feature. Vendor links are listed on this page when they are known.
This page lists the public facts about CVE-2026-3891. Atlas does not run a check for it, so nothing here says whether a particular site is affected.