CVE-2021-24985

Easy Forms for Mailchimp <= 6.8.5 - Reflected Cross-Site Scripting

2021-12-21 00:00

Strategic Overview

Status: Patched in 6.8.6
Affected Plugin: Easy Forms for Mailchimp
Affected Version: < 6.8.6
CVSS: 6.1Medium
Weakness type: CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE: CVE-2021-24985

View all Easy Forms for Mailchimp vulnerabilities

At a glance

CVE-2021-24985 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Easy Forms for Mailchimp WordPress plugin, affecting versions < 6.8.6. It carries a CVSS score of 6.1 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 6.8.6; sites on affected versions should update now. Disclosed December 2021, reported by ZhongFu Su.

Vulnerability Overview

The Easy Forms for Mailchimp WordPress plugin before 6.8.6 does not sanitise and escape the field_name and field_type parameters before outputting them back in attributes, leading to Reflected Cross-Site Scripting issues

Technical Analysis

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

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

Reaching this weakness in Easy Forms for Mailchimp < 6.8.6 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 Easy Forms for Mailchimp the fix is 6.8.6: builds < 6.8.6 are affected, anything from 6.8.6 onward is not.

Remediation

Update to version 6.8.6, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Easy Forms for Mailchimp: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Easy Forms for Mailchimp 6.8.6 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-24985 https://www.wordfence.com/threat-intel/vulnerabilities/id/873b6ace-0377-42d8-a6c5-3fe0226cebc5 https://nvd.nist.gov/vuln/detail/CVE-2021-24985

Related records

Same weakness class

Other vulnerabilities in Easy Forms for Mailchimp

CVSS Vector

6.1

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

Base

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

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