CVE-2026-11901 (GCVE-0-2026-11901)

Vulnerability from cvelistv5 – Published: 2026-07-11 05:35 – Updated: 2026-07-14 14:26
VLAI
Title
WP Hotel Booking <= 2.3.1 - Unauthenticated Insufficient Verification of Data Authenticity to Payment Bypass via PayPal IPN Handler
Summary
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
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-14 14:25 UTC
CWE
  • CWE-345 - Insufficient Verification of Data Authenticity
Assigner
Wordfence CNA under the mitre root
CNA scorecard C 65/100 over 2313 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
thimpress WP Hotel Booking Affected: 0 , ≤ 2.3.1 (semver)
guessed Create a notification for this product.
Credits
valent1
Show details on NVD website
To clipboard 

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