CVE-2021-24166

Ninja Forms Contact Form <= 3.4.33 - Cross-Site Request Forgery to OAuth Service Disconnection

2021-02-16 00:00

Strategic Overview

Status: Patched in 3.4.34
Affected Plugin: Ninja Forms – The Contact Form Builder That Grows With You
Affected Version: < 3.4.34
CVSS: 5.4Medium
Weakness type: CWE-352 · Cross-Site Request Forgery (CSRF)
CVE: CVE-2021-24166

View all Ninja Forms – The Contact Form Builder That Grows With You vulnerabilities

At a glance

CVE-2021-24166 is a medium-severity Cross-Site Request Forgery (CSRF) vulnerability in the Ninja Forms WordPress plugin, affecting versions < 3.4.34. It carries a CVSS score of 5.4 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 3.4.34; sites on affected versions should update now. Disclosed February 2021, reported by Chloe Chamberland.

Vulnerability Overview

The wp_ajax_nf_oauth_disconnect from the Ninja Forms Contact Form – The Drag and Drop Form Builder for WordPress WordPress plugin before 3.4.34 had no nonce protection making it possible for attackers to craft a request to disconnect a site's OAuth connection.

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-352: Cross-Site Request Forgery (CSRF)

Reaching this weakness in Ninja Forms < 3.4.34 takes a caller who can reach the endpoint. Cross-site request forgery abuses the fact that browsers attach a victim's cookies to any request, so a state-changing action that only checks who you are, not whether you meant to act, can be triggered from another site.

An attacker who gets a logged-in user to load a crafted page can perform that action as them, with the impact scaling to whatever the victim's role is allowed to do. For Ninja Forms the fix is 3.4.34: builds < 3.4.34 are affected, anything from 3.4.34 onward is not.

Remediation

Update to version 3.4.34, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Ninja Forms: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Ninja Forms 3.4.34 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-24166 https://www.wordfence.com/threat-intel/vulnerabilities/id/b1faf343-1859-4bee-a2d5-f494f44c70ad https://nvd.nist.gov/vuln/detail/CVE-2021-24166

Related records

Same weakness class

Other vulnerabilities in Ninja Forms – The Contact Form Builder That Grows With You

CVSS Vector

5.4

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionRequired
ScopeUnchanged
ConfidentialityNone
IntegrityLow
AvailabilityLow

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