Masteriyo LMS: Improper Authentication
CVE-2026-13332 is a critical-severity improper authentication vulnerability in Masteriyo LMS, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 2.3.1 as the first without the flaw, so updating Masteriyo LMS to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.42% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Masteriyo LMS to 2.3.1 or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Masteriyo LMS | Masteriyo LMS | before 2.3.1 | 2.3.1 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N. Scored by CISA (ADP).
Official description
The Masteriyo LMS WordPress plugin before 2.3.1 does not correctly verify authorization on an unauthenticated AJAX action used to clear user sessions, allowing unauthenticated attackers to terminate the active sessions (force-logout) of any user on the site, including administrators.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Authentication
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
How developers prevent this class of flaw
- Use an authentication framework or library such as the OWASP ESAPI Authentication feature.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: total).
References
Other references
Other vulnerabilities in Masteriyo LMS
- 9.9 Critical severity
Recent Improper Authentication vulnerabilities
- 8.8 High severity
- 8.2 High severity
- 7.5 High severity
- 8.1 High severity
- 8.4 High severity
- 9.1 Critical severity
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