CVE-2026-81026Public exploitNetwork attack vectorHinoki check available

Paid-content access via unchecked PayPal IPN

Published Aug 29, 2026 · Updated Aug 29, 2026

Payment bypass in StylemixThemes MasterStudy LMS before 3.7.40 allows remote attackers to obtain paid course access via PayPal IPN. The PayPal IPN order-completion handler treats a verified notification as sufficient without matching its amount, receiver, currency, or status to the local order. Remote attackers need a PayPal-verified token payment; successful exploitation completes the full-price order and grants its course enrollment.

CVSS severity4.8
Medium
EPSS probability0.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Payment bypass in StylemixThemes MasterStudy LMS before 3.7.40 allows remote attackers to obtain paid course access via PayPal IPN. The PayPal IPN order-completion handler treats a verified notification as sufficient without matching its amount, receiver, currency, or status to the local order. Remote attackers need a PayPal-verified token payment; successful exploitation completes the full-price order and grants its course enrollment.

The record

CVE
CVE-2026-81026
Published
Aug 29, 2026
Updated
Aug 29, 2026
Vendor
StylemixThemes
Product
MasterStudy LMS
Classifications
CWE-284
Attack vector
network
Privileges
unauthenticated

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 <3.7.40

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

StylemixThemes · MasterStudy LMSversion=0 <3.7.40

Published CVSS scores

4.8CISA ADPCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/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 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 exploitPublished

Weakness, pattern, technique

CWE-284Improper Access Control

Public exploit references

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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