matrixaddons Easy Invoice Plugin up to 2.1.19 Quote Management nonce authorization

Summaryinfo

A vulnerability labeled as critical has been found in matrixaddons Easy Invoice Plugin up to 2.1.19. Impacted is the function easy_invoice_accept_quote/easy_invoice_decline_quote of the component Quote Management. The manipulation of the argument nonce results in authorization. This vulnerability is cataloged as CVE-2026-9021. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as critical, was found in matrixaddons Easy Invoice Plugin up to 2.1.19. Affected is the function easy_invoice_accept_quote/easy_invoice_decline_quote of the component Quote Management. The manipulation of the argument nonce with an unknown input leads to a authorization vulnerability. CWE is classifying the issue as CWE-862. The product does not perform an authorization check when an actor attempts to access a resource or perform an action. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at wordfence.com. This vulnerability is traded as CVE-2026-9021 since 05/19/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 07/09/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Vendor

• matrixaddons

Name

• Easy Invoice Plugin

Version

• 2.1.0
• 2.1.1
• 2.1.2
• 2.1.3
• 2.1.4
• 2.1.5
• 2.1.6
• 2.1.7
• 2.1.8
• 2.1.9
• 2.1.10
• 2.1.11
• 2.1.12
• 2.1.13
• 2.1.14
• 2.1.15
• 2.1.16
• 2.1.17
• 2.1.18
• 2.1.19

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CPE 2.2info

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