Cross-site Scripting (XSS)Weakness · CWE-79

CVE-2026-57330

MEDIUM · 6.5 CVSS v3.1 Published 2026-06-29
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
69/100
Remediation priority · Elevated
Remotely reachable 7 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Subscriber Cross Site Scripting (XSS) in MasterStudy LMS <= 3.7.27 versions.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

A stored Cross Site Scripting (XSS) vulnerability exists in MasterStudy LMS plugin versions 3.7.27 and below. Authenticated users with Subscriber-level privileges can inject malicious JavaScript code through input fields that lack proper sanitization. The malicious script executes when other users (including administrators) view the affected content.

MitigationUpdate MasterStudy LMS to a version beyond 3.7.27 that contains the security patch. If no update is available, implement input sanitization using WordPress sanitization functions (such as sanitize_text_field() and esc_attr()) on all user-supplied input fields within the plugin.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
Low

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Verify MasterStudy LMS is installed
    Navigate to WordPress admin dashboard > Plugins > Installed Plugins and locate MasterStudy LMS in the list
    Affected if The plugin is not installed or not present in the plugins list, then the environment is not affected by this specific vulnerability
  2. Check the installed version
    In the Plugins list, look for the version number displayed under the MasterStudy LMS plugin name, or check the plugin's main file header for the Version constant
    Affected if The installed version is 3.7.27 or lower; versions 3.7.27 and below are affected by this stored XSS vulnerability
  3. Confirm the plugin is active
    In the Plugins list, verify that MasterStudy LMS shows as 'Active' under the plugin status
    Affected if The plugin is active - an inactive plugin would not allow the XSS to be triggered even if the vulnerable code exists
  4. Identify Subscriber-level user accounts
    Navigate to WordPress admin > Users and review the user list to identify any accounts with the Subscriber role
    Affected if Subscriber-level users exist in the system - these users have the minimum privileges required to inject the malicious script according to the CVE description
  5. Audit user input fields for sanitization
    Review the MasterStudy LMS plugin code (specifically PHP files handling form submissions) for use of WordPress sanitization functions like sanitize_text_field(), esc_attr(), or esc_html() on user-supplied input
    Affected if Input fields lack proper sanitization - the vulnerability exists precisely where these functions are missing on user input fields within the plugin

The environment is affected if MasterStudy LMS version 3.7.27 or below is installed and active, particularly when Subscriber-level users exist and user input fields in the plugin lack sanitization functions.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update MasterStudy LMS to a version beyond 3.7.27 that contains the security patch. If no update is available, implement input sanitization using WordPress sanitization functions (such as sanitize_text_field() and esc_attr()) on all user-supplied input fields within the plugin.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation3.0 h
  • Testing2.0 h
  • Review / QA1.0 h
8.0 hours of engineering $1,420
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Scan for this in your stack

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dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-57330 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data