CVE-2021-24308

LMS by LifterLMS – Online Course, Membership & Learning Management System Plugin <= 4.21.0 - Stored Cross-Site Scripting

2021-05-10 00:00

Strategic Overview

Status: Patched in 4.21.1
Affected Plugin: LifterLMS – WP LMS for eLearning, Online Courses, & Quizzes
Affected Version: < 4.21.1
CVSS: 5.4Medium
Weakness type: CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE: CVE-2021-24308

View all LifterLMS – WP LMS for eLearning, Online Courses, & Quizzes vulnerabilities

At a glance

CVE-2021-24308 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the LifterLMS WordPress plugin, affecting versions < 4.21.1. It carries a CVSS score of 5.4 (reachable over the network; low attack complexity). The issue is fixed in version 4.21.1; sites on affected versions should update now. Disclosed May 2021, reported by captain_hook.

Vulnerability Overview

The 'State' field of the Edit profile page of the LMS by LifterLMS – Online Course, Membership & Learning Management System Plugin for WordPress plugin before 4.21.1 is not properly sanitised when output in the About section of the profile page, leading to a stored Cross-Site Scripting issue. This could allow low privilege users (such as students) to elevate their privilege via an XSS attack when an admin will view their profile.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed.

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

LifterLMS < 4.21.1 carries this weakness at State, and reaching it takes a caller who can reach the endpoint. Cross-site scripting happens when input from a request is written into a page without being escaped for the context it lands in, so the browser parses attacker-supplied text as markup or script.

Injected script runs with the privileges of whoever views the affected page, which is how these flaws turn into administrator session theft, silent account creation or persistent backdoors in page content. For LifterLMS the fix is 4.21.1: builds < 4.21.1 are affected, anything from 4.21.1 onward is not.

Remediation

Update to version 4.21.1, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to LifterLMS: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: LifterLMS 4.21.1 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-24308 https://www.wordfence.com/threat-intel/vulnerabilities/id/86b54c46-a637-4fc4-8d48-a02383c9814b https://nvd.nist.gov/vuln/detail/CVE-2021-24308

Related records

Same weakness class

Other vulnerabilities in LifterLMS – WP LMS for eLearning, Online Courses, & Quizzes

CVSS Vector

5.4

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionRequired
ScopeChanged
ConfidentialityLow
IntegrityLow
AvailabilityNone

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