CVE-2026-11901WP Hotel Booking <= 2.3.1 - Unauthenticated Insufficient Verification of Data Authenticity to Payment Bypass via PayPal IPN Handler
- 5.3MediumCVSS base score
- 0.26%Exploitation in 30 daysEPSS · top 82% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By Wordfence
- 31 days later
· 31 days later
Published
- 3 days later
· 3 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| WordfenceCNA (assigner) | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
| NVDNVD · Deferred | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.26% · top 82% of all CVEs (15 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.3.
Affected products
- affected ≤ 2.3.1
References
References10
- https://www.wordfence.com/threat-intel/vulnerabilities/id/191ec7ea-6ca7-4943-8709-f372ae5a81c7?source=cve (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.0/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L173 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.0/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L194 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.0/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L186 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.0/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L253 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.1/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L173 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.1/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L194 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.1/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L186 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/wp-hotel-booking/tags/2.3.1/includes/gateways/paypal/class-wphb-payment-gateway-paypal.php#L253 (opens in a new tab)
- https://plugins.trac.wordpress.org/changeset?reponame=&old=3582839%40wp-hotel-booking&new=3582839%40wp-hotel-booking (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-43149 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-11901)Record last updated .