AlternativeCommerce PayPal Checkout security updates, in plain English

AlternativeCommerce PayPal Checkout

16 sites report using it · on drupal.org · 1 security update explained here

This module connects an online store to a popular payment service to process customer purchases.

Below is every security update for AlternativeCommerce PayPal Checkout that this site has covered, newest first. Each one says who could exploit it, whether it applies to your site, how urgent it is, and what to tell your developer. If your site uses this module and you are not sure which version, that is the first question to ask whoever looks after it.

AlternativeCommerce PayPal Checkout

Moderately critical · 16 sites report using it · SA-CONTRIB-2026-300 · on drupal.org · Week of 4 November 2026

The module does not properly check incoming messages from the payment service. Anyone could send a fake message to mark an order as paid without actually spending any money. They would not be able to view hidden information.

Who could do thisAnyone visiting the site. No login needed.
Does it apply to youAny site using this module.
Has it been used in attacksNo sign of it.
How urgentDrupal rates this moderately critical. Include it in your next routine update, within the month.

Tell your developerUpdate AlternativeCommerce PayPal Checkout to 1.1.1.

For developers: what the fix changed

The fix adds webhook signature verification in `src/PayPal.php` and `src/Controller/Pages.php` to ensure requests originate from PayPal. It also introduces strict validation in `src/Controller/ApiPage.php` and `src/PayPal.php` to ensure the PayPal order details match the local payment record before marking an order as paid.

Also in this release Added webhook ID configuration, improved session handling for checkout snapshots, and added unit tests.

1.1.0 to 1.1.1 1 commit, 11 files including 2 tests.

basket_paypal.libraries.yml +5 −0
config/install/basket_paypal.settings.yml +2 −0
src/Controller/ApiPage.php +209 −50 fix
src/Controller/Pages.php +132 −82 fix
src/Form/PaymentForm.php +61 −12
src/Form/SettingsForm.php +22 −5
src/PayPal.php +137 −1 fix
src/Services/PayPalJs.php +14 −3
templates/basket-paypal-buttons.html.twig +1 −0

Full diff, 1.1.0 to 1.1.1

The comparison is against the release immediately before the fix. If your site is on an older release, more will have changed.

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AlternativeCommerce PayPal Checkout

AlternativeCommerce PayPal Checkout

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