CVE-2026-87091: uscnanbu welcart e-commerce Cross-site Scripting

Vulnerability summary

CVE-2026-87091 is a high (CVSS 7.2) Cross-site Scripting vulnerability in uscnanbu welcart e-commerce. EPSS estimates a 0.31% chance of exploitation in the next 30 days, higher than 22.8% of scored vulnerabilities. Fixed in 2.12.3.

Timeline

1. 03-10-2026
   PublishedVulnerability first disclosed.
2. 03-10-2026
   Last modifiedVulnerability information updated.

Description

The Welcart e-Commerce plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Settlement Notification Parameters in all versions up to, and including, 2.12.2 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The IPN endpoint accepts the 'rel' and 'option' parameters with no authentication, nonce validation, or signature verification, meaning any unauthenticated attacker can directly submit malicious payloads that are stored and later rendered in the administrator's settlement error log view.

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.