CVE-2026-81338

MEDIUMPre-NVD 4.64.6—
EchelonGraph scoreHIGH confidence

Score 4.6 from GitHub Security Advisory published 2026-09-23. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 4.6; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 5 sources updated this week
4.6EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 4.6Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
4.6
EG Score
4.6(high)
EG Risk
21(Track)
EG Risk 21/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity46% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
1%
KEV
Not listed

Published

September 23, 2026

Last Modified

September 23, 2026

Advisory Details (1)

Auto-updated Sep 23, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic🟡 PoC Available

MasterStudy LMS < 3.7.50 – Subscriber+ Stored HTML Injection via Course Discussions | CVE 2026-81338 | Plugin Vulnerabilities

https://wpscan.com/vulnerability/e8494c71-fb0f-4ab9-a8b7-8db3745a2d9b/

Vendor Advisories for CVE-2026-81338(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 13× in last 7d / 13× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-24 20:18 UTCEG score recompute
  2. 2026-09-24 20:18 UTCGHSA enrichment
  3. 2026-09-24 14:04 UTCEPSS rescore
  4. 2026-09-23 18:20 UTCEG score recompute
  5. 2026-09-23 18:19 UTCGHSA enrichment
  6. 2026-09-23 17:54 UTCEPSS rescore
  7. 2026-09-23 11:23 UTCGHSA enrichment
  8. 2026-09-23 11:07 UTCEG score recompute▲ 4.60
  9. 2026-09-23 11:06 UTCGHSA enrichment
  10. 2026-09-23 11:06 UTCMITRE cvelistV5CVSS v3 → 4.6 · severity → MEDIUM
  11. 2026-09-23 06:17 UTCNVD update
  12. 2026-09-23 06:06 UTCEG score recompute
  13. 2026-09-23 06:06 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-81338?
CVE-2026-81338 is a medium vulnerability published on September 23, 2026. 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…
When was CVE-2026-81338 disclosed?
CVE-2026-81338 was first published in the National Vulnerability Database on September 23, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-81338 actively exploited?
CVE-2026-81338 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 99.5% of all scored CVEs.
What is the CVSS score of CVE-2026-81338?
CVE-2026-81338 has a CVSS v3.1 base score of 4.6 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-81338?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-81338, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-81338

Explore →

Is Your Infrastructure Affected by CVE-2026-81338?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Book a Demo →Browse All CVEs