CVE-2026-8840Network attack vector

Unauthenticated payment manipulation via unchecked AJAX handler

Published Aug 15, 2026 · Updated Aug 15, 2026

Missing authorization in WpDevArt Booking Calendar 3.2.36 and earlier allows remote attackers to alter reservation payment states. The wpdevart_payment AJAX handler accepts attacker-supplied payment status and transaction data and writes it directly to the payments table without verifying authorization. No authentication is required; payment manipulation and transactional email dispatch are always exposed, while reservation auto-approval also requires the enable_psuccess_approval option.

CVSS severity5.3
Medium
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in WpDevArt Booking Calendar 3.2.36 and earlier allows remote attackers to alter reservation payment states. The wpdevart_payment AJAX handler accepts attacker-supplied payment status and transaction data and writes it directly to the payments table without verifying authorization. No authentication is required; payment manipulation and transactional email dispatch are always exposed, while reservation auto-approval also requires the enable_psuccess_approval option.

The record

CVE
CVE-2026-8840
Published
Aug 15, 2026
Updated
Aug 15, 2026
Vendor
WpDevArt
Product
Booking calendar, Appointment Booking System
Classifications
CWE-862, T1565.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=3.2.36

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

WpDevArt · Booking calendar, Appointment Booking Systemversion=0 <=3.2.36

Published CVSS scores

5.3WordfenceCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-862Missing Authorization
T1565.001Stored Data Manipulation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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