All vulnerabilities
CVE-2026-104641

Simple Shopping Cart < 5.3.3 - Unauthenticated Payment Bypass via Unverified PayPal IPN Recipient

Unknown Simple Shopping Cart
Open in ThreatlineRecord JSON
CVSS
5.3Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.11%Chance of exploitation activity in the next 30 days, higher than 1% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in5.3.3Fixed versionCVE List
Published21 Oct 2026Updated 21 Oct 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

The Simple Shopping Cart WordPress plugin before 5.3.3 does not verify that a PayPal payment notification is for a payment received by the site owner's PayPal account in its default configuration, allowing unauthenticated attackers to have their orders marked as paid using a payment made to an account they control.

Text from CVE List

Affected versions 1

  • Simple Shopping Cartaffected: all versions before 5.3.3CVE List

References 1