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Fencer Intel
medium 4.6

CVE-2026-81338 json

MasterStudy LMS < 3.7.50 - Subscriber+ Stored HTML Injection via Course Discussions

published last mo. modified last mo. also EUVD-2026-85028

cvss
4.6
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 2%
public exploits
0
none known

Summary

The MasterStudy LMS WordPress Plugin WordPress plugin before 3.7.50 does not properly sanitise and restrict HTML in user-submitted content before storing it and rendering it to other users, allowing users with subscriber-level accounts and above to perform stored HTML injection, such as embedding iframes, that can be leveraged for phishing and content spoofing against other users viewing the content.

Patch / fix

  • Unknown MasterStudy LMS WordPress Plugin 3.7.50

Is CVE-2026-81338 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
last mo.

Exploit prediction

0.12% chance of exploitation in the next 30 days, higher than 2% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • wpscan.com https://wpscan.com/vulnerability/e8494c71-fb0f-4ab9-a8b7-8db3745a2d9b/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CISA ADP 3.1 4.6 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
CNA 3.1 4.6 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N

Affected products

  • Unknown MasterStudy LMS WordPress Plugin

Classification

Weakness
  • CWE-345 Insufficient Verification of Data Authenticity
Technology feeds

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.