CVE-2021-20781

Meta Data Filter & Taxonomies Filter <= 1.2.7.2 - Cross-Site Request Forgery

2021-07-14 00:00
Ryoma Nishioka

Strategic Overview

Status
Patched in 2.2.8
Affected Plugin
MDTF – Meta Data and Taxonomies Filter
Affected Version
< 2.2.8
CVSS
8.8High
Weakness type
CWE-352 · Cross-Site Request Forgery (CSRF)
CVE
CVE-2021-20781
View all MDTF – Meta Data and Taxonomies Filter vulnerabilities

At a glance

CVE-2021-20781 is a high-severity Cross-Site Request Forgery (CSRF) vulnerability in the MDTF WordPress plugin, affecting versions < 2.2.8. It carries a CVSS score of 8.8 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires no authentication. The issue is fixed in version 2.2.8; sites on affected versions should update now. Disclosed July 2021, reported by Ryoma Nishioka.

Vulnerability Overview

The Meta Data Filter & Taxonomies Filter plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions versions prior to v.2.2.8. This is due to missing or incorrect nonce validation on the draw_settings_page() function. This makes it possible for unauthenticated attackers to inject malicious JavaScript via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.

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. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.

CWE-352: Cross-Site Request Forgery (CSRF)

MDTF < 2.2.8 carries this weakness at draw_settings_page(), and reaching it 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 MDTF the fix is 2.2.8: builds < 2.2.8 are affected, anything from 2.2.8 onward is not.

Remediation

Update to version 2.2.8, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to MDTF: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: MDTF 2.2.8 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-20781https://www.wordfence.com/threat-intel/vulnerabilities/id/77b7fb02-1b79-4b0b-99ab-fa042e86391ahttps://nvd.nist.gov/vuln/detail/CVE-2021-20781

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C