CVE-2021-24716

Modern Events Calendar Lite <= 5.22.2 - Authenticated Stored Cross Site Scripting

2021-09-29 00:00
Shivam Rai

Strategic Overview

Status
Patched in 5.22.3
Affected Version
<= 5.22.2
CVSS
5.4Medium
Weakness type
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE
CVE-2021-24716
View all Modern Events Calendar Lite vulnerabilities

At a glance

CVE-2021-24716 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Modern Events Calendar Lite WordPress plugin, affecting versions <= 5.22.2. It carries a CVSS score of 5.4 (reachable over the network; low attack complexity). Exploitation requires an authenticated account. The issue is fixed in version 5.22.3; sites on affected versions should update now. Disclosed September 2021, reported by Shivam Rai.

Vulnerability Overview

The Modern Events Calendar Lite WordPress plugin before 5.22.3 does not properly sanitize or escape values set by users with access to adjust settings withing wp-admin.

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')

Reaching this weakness in Modern Events Calendar Lite <= 5.22.2 takes any authenticated account. 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 Modern Events Calendar Lite the fix is 5.22.3: builds <= 5.22.2 are affected, anything from 5.22.3 onward is not.

Remediation

Update to version 5.22.3, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Modern Events Calendar Lite: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Modern Events Calendar Lite 5.22.3 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

Related records

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