CVE-2026-16986Network attack vector

Unauthenticated underpayment via client-controlled price calculation

Published Aug 26, 2026 · Updated Aug 26, 2026

Improper access control in Booking Package before 1.7.25 allows remote attackers to underpay for bookings through crafted requests. The payment workflow calculates the expected charge from request-supplied service and option costs instead of comparing the submitted amount with the server-stored price. An unauthenticated booking request is sufficient, and successful exploitation reduces the charged amount without changing the stored service price.

CVSS severity5.3
Medium
EPSS probability0.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in Booking Package before 1.7.25 allows remote attackers to underpay for bookings through crafted requests. The payment workflow calculates the expected charge from request-supplied service and option costs instead of comparing the submitted amount with the server-stored price. An unauthenticated booking request is sufficient, and successful exploitation reduces the charged amount without changing the stored service price.

The record

CVE
CVE-2026-16986
Published
Aug 26, 2026
Updated
Aug 26, 2026
Vendor
MASAAKI TANAKA
Product
Booking Package
Classifications
CWE-284, T1565.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 26, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 26, 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 <1.7.25

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

MASAAKI TANAKA · Booking Packageversion=0 <1.7.25

Published CVSS scores

5.3CISA ADPCVSS: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

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-284Improper Access Control
T1565.002Transmitted 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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