{"id":"CVE-2026-11901","aliases":["EUVD-2026-43149","GHSA-8frr-75wq-jfgf"],"status":"published","title":"WP Hotel Booking \u003c= 2.3.1 - Unauthenticated Insufficient Verification of Data Authenticity to Payment Bypass via PayPal IPN Handler","description":"The WP Hotel Booking plugin for WordPress is vulnerable to Insufficient Verification of Data Authenticity in all versions up to, and including, 2.3.1. This is due to the `web_hook_process_paypal_standard()` IPN handler selecting its PayPal validation endpoint from the attacker-controlled `$_REQUEST['test_ipn']` parameter, force-upgrading any `pending` transaction to `completed` when `test_ipn=1`, and omitting post-verification checks on `receiver_email`, `mc_currency`, and `txn_id` uniqueness after receiving a `VERIFIED` response from PayPal. This makes it possible for unauthenticated attackers to mark arbitrary hotel bookings as fully paid without submitting genuine payment to the merchant — either by routing IPN validation through PayPal's sandbox using a free sandbox account, or by replaying a previously verified IPN from a nominal payment to an attacker-controlled PayPal account. An attacker requires only a free PayPal sandbox account (or any PayPal account) to obtain a `VERIFIED` response; no site credentials or special configuration are needed.","severity":{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00259,"percentile":0.17726,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-345"],"published":"2026-07-11T05:35:44Z","modified":"2026-07-14T15:16:56Z","products":[{"vendor":"thimpress","product":"wp hotel booking"}],"references":[{"url":"https://www.wordfence.com/threat-intel/vulnerabilities/id/191ec7ea-6ca7-4943-8709-f372ae5a81c7?source=cve"},{"url":"https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.0/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L173"},{"url":"https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.0/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L194"},{"url":"https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.0/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L186"},{"url":"https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.0/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L253"},{"url":"https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.1/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L173"},{"url":"https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.1/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L194"},{"url":"https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.1/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L186"},{"url":"https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.1/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L253"},{"url":"https://plugins.trac.wordpress.org/changeset?reponame=\u0026old=3582839%40wp-hotel-booking\u0026new=3582839%40wp-hotel-booking"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-11901"},{"url":"https://github.com/advisories/GHSA-8frr-75wq-jfgf"}],"sources":{"cve":[{"id":"CVE-2026-11901","title":"WP Hotel Booking \u003c= 2.3.1 - Unauthenticated Insufficient Verification of Data Authenticity to Payment Bypass via PayPal IPN Handler","description":"The WP Hotel Booking plugin for WordPress is vulnerable to Insufficient Verification of Data Authenticity in all versions up to, and including, 2.3.1. This is due to the `web_hook_process_paypal_standard()` IPN handler selecting its PayPal validation endpoint from the attacker-controlled `$_REQUEST['test_ipn']` parameter, force-upgrading any `pending` transaction to `completed` when `test_ipn=1`, and omitting post-verification checks on `receiver_email`, `mc_currency`, and `txn_id` uniqueness after receiving a `VERIFIED` response from PayPal. This makes it possible for unauthenticated attackers to mark arbitrary hotel bookings as fully paid without submitting genuine payment to the merchant — either by routing IPN validation through PayPal's sandbox using a free sandbox account, or by replaying a previously verified IPN from a nominal payment to an attacker-controlled PayPal account. An attacker requires only a free PayPal sandbox account (or any PayPal account) to obtain a `VERIFIED` response; no site credentials or special configuration are needed.","status":"published","published":"2026-07-11T05:35:44.057Z","modified":"2026-07-14T14:26:01.248Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-345"],"updated_at":"2026-11-02T14:20:04.809935Z"}],"euvd":[{"id":"EUVD-2026-43149","description":"The WP Hotel Booking plugin for WordPress is vulnerable to Insufficient Verification of Data Authenticity in all versions up to, and including, 2.3.1. This is due to the `web_hook_process_paypal_standard()` IPN handler selecting its PayPal validation endpoint from the attacker-controlled `$_REQUEST['test_ipn']` parameter, force-upgrading any `pending` transaction to `completed` when `test_ipn=1`, and omitting post-verification checks on `receiver_email`, `mc_currency`, and `txn_id` uniqueness after receiving a `VERIFIED` response from PayPal. This makes it possible for unauthenticated attackers to mark arbitrary hotel bookings as fully paid without submitting genuine payment to the merchant — either by routing IPN validation through PayPal's sandbox using a free sandbox account, or by replaying a previously verified IPN from a nominal payment to an attacker-controlled PayPal account. An attacker requires only a free PayPal sandbox account (or any PayPal account) to obtain a `VERIFIED` response; no site credentials or special configuration are needed.","status":"published","published":"2026-07-11T05:35:44Z","modified":"2026-07-14T14:26:01Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T18:20:00.206712Z"}],"ghsa":[{"id":"GHSA-8frr-75wq-jfgf","title":"The WP Hotel Booking plugin for WordPress is vulnerable to Insufficient Verification of Data...","description":"The WP Hotel Booking plugin for WordPress is vulnerable to Insufficient Verification of Data Authenticity in all versions up to, and including, 2.3.1. This is due to the `web_hook_process_paypal_standard()` IPN handler selecting its PayPal validation endpoint from the attacker-controlled `$_REQUEST['test_ipn']` parameter, force-upgrading any `pending` transaction to `completed` when `test_ipn=1`, and omitting post-verification checks on `receiver_email`, `mc_currency`, and `txn_id` uniqueness after receiving a `VERIFIED` response from PayPal. This makes it possible for unauthenticated attackers to mark arbitrary hotel bookings as fully paid without submitting genuine payment to the merchant — either by routing IPN validation through PayPal's sandbox using a free sandbox account, or by replaying a previously verified IPN from a nominal payment to an attacker-controlled PayPal account. An attacker requires only a free PayPal sandbox account (or any PayPal account) to obtain a `VERIFIED` response; no site credentials or special configuration are needed.","status":"published","published":"2026-07-11T09:34:18Z","modified":"2026-07-11T09:34:25Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-345"],"updated_at":"2026-11-02T15:09:24.04976Z"}],"nvd":[{"id":"CVE-2026-11901","description":"The WP Hotel Booking plugin for WordPress is vulnerable to Insufficient Verification of Data Authenticity in all versions up to, and including, 2.3.1. This is due to the `web_hook_process_paypal_standard()` IPN handler selecting its PayPal validation endpoint from the attacker-controlled `$_REQUEST['test_ipn']` parameter, force-upgrading any `pending` transaction to `completed` when `test_ipn=1`, and omitting post-verification checks on `receiver_email`, `mc_currency`, and `txn_id` uniqueness after receiving a `VERIFIED` response from PayPal. This makes it possible for unauthenticated attackers to mark arbitrary hotel bookings as fully paid without submitting genuine payment to the merchant — either by routing IPN validation through PayPal's sandbox using a free sandbox account, or by replaying a previously verified IPN from a nominal payment to an attacker-controlled PayPal account. An attacker requires only a free PayPal sandbox account (or any PayPal account) to obtain a `VERIFIED` response; no site credentials or special configuration are needed.","status":"published","published":"2026-07-11T07:16:45.347Z","modified":"2026-07-14T15:16:56.343Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-345"],"updated_at":"2026-11-02T14:12:28.771746Z"}]}}