CVE-2023-4278Public exploitNetwork attack vector

Unauthenticated instructor account creation via trusted registration flag

Published Sep 11, 2023 · Updated Apr 23, 2025

Privilege escalation in StylemixThemes MasterStudy LMS before 3.0.18 allows remote attackers to create instructor accounts during registration. The registration handler trusts the client-controlled become_instructor field even when instructor registration and pre-moderation are disabled, assigning the new account instructor privileges. No authentication or user interaction is required; the new instructor can create courses and submit blog posts for review.

CVSS severity7.5
High
EPSS probability6.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Privilege escalation in StylemixThemes MasterStudy LMS before 3.0.18 allows remote attackers to create instructor accounts during registration. The registration handler trusts the client-controlled become_instructor field even when instructor registration and pre-moderation are disabled, assigning the new account instructor privileges. No authentication or user interaction is required; the new instructor can create courses and submit blog posts for review.

The record

CVE
CVE-2023-4278
Published
Sep 11, 2023
Updated
Apr 23, 2025
Vendor
StylemixThemes
Product
MasterStudy LMS
Classifications
CWE-269, T1136
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 11, 2023CVE publishedPublication date reported by the CVE source.
  2. Apr 23, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=0 <3.0.18

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

StylemixThemes · MasterStudy LMSversion=0 <3.0.18

Published CVSS scores

7.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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-269Improper Privilege Management
T1136Create Account

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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