CVE-2026-13332Public exploitNetwork attack vector

Unauthenticated session termination via exposed clearance nonce

Published Jul 27, 2026 · Updated Jul 27, 2026

Improper authentication in Masteriyo LMS before 2.3.1 allows remote attackers to terminate any WordPress user's active sessions. When Limit Login Session is enabled, masteriyo_login discloses a masteriyo_clear_sessions nonce before password verification for a known non-admin account at its session limit. The unauthenticated masteriyo_clear_sessions AJAX action accepts that nonce with an arbitrary user_id and destroys the target's session tokens, allowing repeated requests to keep administrators or other users logged out.

CVSS severity9.1
Critical
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication in Masteriyo LMS before 2.3.1 allows remote attackers to terminate any WordPress user's active sessions. When Limit Login Session is enabled, masteriyo_login discloses a masteriyo_clear_sessions nonce before password verification for a known non-admin account at its session limit. The unauthenticated masteriyo_clear_sessions AJAX action accepts that nonce with an arbitrary user_id and destroys the target's session tokens, allowing repeated requests to keep administrators or other users logged out.

The record

CVE
CVE-2026-13332
Published
Jul 27, 2026
Updated
Jul 27, 2026
Vendor
ThemeGrill
Product
Masteriyo LMS
Classifications
CWE-287, T1531
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 27, 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 <2.3.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ThemeGrill · Masteriyo LMSversion=0 <2.3.1

Published CVSS scores

5.3WordfenceCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
9.1WPScan CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/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.

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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-287Improper Authentication
T1531Account Access Removal

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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