CVE-2026-18234Network attack vectorHinoki check available

Unpaid order completion via unchecked wallet handling

Published Aug 29, 2026 · Updated Aug 29, 2026

Missing authorization in FluxBuilder MStore API before 4.21.1 allows remote authenticated users to mark arbitrary orders as paid. The wallet payment handler accepts a requester-selected order without checking ownership and, for most payment methods, records payment without deducting the requester's wallet balance. Subscriber-level access is sufficient, and exploitation changes the chosen order's payment state without transferring funds.

CVSS severity6.5
Medium
EPSS probability0.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Missing authorization in FluxBuilder MStore API before 4.21.1 allows remote authenticated users to mark arbitrary orders as paid. The wallet payment handler accepts a requester-selected order without checking ownership and, for most payment methods, records payment without deducting the requester's wallet balance. Subscriber-level access is sufficient, and exploitation changes the chosen order's payment state without transferring funds.

The record

CVE
CVE-2026-18234
Published
Aug 29, 2026
Updated
Aug 29, 2026
Vendor
FluxBuilder
Product
MStore API
Classifications
CWE-862, T1565.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 29, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 29, 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 <4.21.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

FluxBuilder · MStore APIversion=0 <4.21.1

Published CVSS scores

6.5CISA ADPCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
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.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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