CVE-2026-9021: Easy Invoice <= 2.1.19 - Unauthenticated Arbitrary Quote Accept/Decline and Invoice Creation via easy_invoice_accept_quote / easy_invoice_decline_quote AJAX Actions

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-09 · updated 2026-07-09
Weakness: CWE-862

Description

The Easy Invoice plugin for WordPress is vulnerable to Missing Authorization in versions up to, and including, 2.1.19. This is due to the plugin registering the easy_invoice_accept_quote and easy_invoice_decline_quote AJAX actions via wp_ajax_nopriv_ hooks and relying solely on a quote-scoped nonce that is rendered into the publicly accessible single quote template, combined with an ownership check that is gated behind an off-by-default Pro option (easy_invoice_pro_restrict_quote_to_client). This makes it possible for unauthenticated attackers to accept or decline arbitrary published quotes — and, depending on the configured accept action, automatically convert them into invoices (and even email them to the client) — by harvesting the per-quote nonce from the public quote page and submitting it to admin-ajax.

Affected products

matrixaddons Easy Invoice – Invoice Generator, PDF Quotes & Payments: through 2.2.19

References

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