CVE-2021-25118

Yoast SEO <= 17.2 - Full Path Disclosure

2021-10-05 00:00

Strategic Overview

Status: Patched in 17.3
Affected Plugin: Yoast SEO – Advanced SEO with real-time guidance and built-in AI
Affected Version: < 17.3
CVSS: 5.3Medium
Weakness type: CWE-200 · Exposure of Sensitive Information to an Unauthorized Actor
CVE: CVE-2021-25118

View all Yoast SEO – Advanced SEO with real-time guidance and built-in AI vulnerabilities

At a glance

CVE-2021-25118 is a medium-severity Exposure of Sensitive Information to an Unauthorized Actor vulnerability in the Yoast SEO WordPress plugin, affecting versions < 17.3. It carries a CVSS score of 5.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 17.3; sites on affected versions should update now. Disclosed October 2021, reported by Fariq Fadillah Gusti Insani (fariqfgi).

Vulnerability Overview

The Yoast SEO plugin for WordPress is vulnerable to Sensitive Data Exposure in versions up to, and including, 17.2 via the /wp/v2/posts REST endpoints that discloses the full internal path of featured images from posts. This makes it possible for unauthenticated attackers to extract sensitive data which consists of full site path information which can be used to exploit other vulnerabilities.

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, and no interaction from a victim user.

CWE-200: Exposure of Sensitive Information to an Unauthorized Actor

Reaching this weakness in Yoast SEO < 17.3 takes a caller who can reach the endpoint. Sensitive information exposure means data the application intended to keep internal is returned to a caller who should not be able to see it.

The disclosed data — credentials, tokens, customer records or internal paths — is usually worth more as material for a follow-up attack than as an end in itself. For Yoast SEO the fix is 17.3: builds < 17.3 are affected, anything from 17.3 onward is not.

Remediation

Update to version 17.3, or a newer patched version

How does WordSec protect against this?

The fix is the thing that ends this: Yoast SEO 17.3 closes this, and updating the plugin is the step that ends it.

Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-25118 https://www.wordfence.com/threat-intel/vulnerabilities/id/f162e046-a7d3-4f2c-899d-6c46cb92c8ee https://nvd.nist.gov/vuln/detail/CVE-2021-25118

Related records

Same weakness class

5.3Yoast SEO <= 3.2.4 Sensitive Data Exposure

Other vulnerabilities in Yoast SEO – Advanced SEO with real-time guidance and built-in AI

CVSS Vector

5.3

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityLow
IntegrityNone
AvailabilityNone

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