CVE-2021-24872

Get Custom Field Values < 4.0 - Arbitrary Post Metadata Access

2021-11-09 00:00

Strategic Overview

Status: Patched in 4.0
Affected Plugin: Get Custom Field Values
Affected Version: < 4.0
CVSS: 6.5Medium
Weakness type: CWE-862 · Missing Authorization
CVE: CVE-2021-24872

View all Get Custom Field Values vulnerabilities

At a glance

CVE-2021-24872 is a medium-severity Missing Authorization vulnerability in the Get Custom Field Values WordPress plugin, affecting versions < 4.0. It carries a CVSS score of 6.5 (reachable over the network; low attack complexity; high confidentiality impact). The issue is fixed in version 4.0; sites on affected versions should update now. Disclosed November 2021, reported by Francesco Carlucci.

Vulnerability Overview

The Get Custom Field Values WordPress plugin before 4.0 allows users with a role as low as Contributor to access other posts metadata without validating the permissions. Eg. contributors can access admin posts metadata.

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 interaction from a victim user. A successful exploit has high impact on confidentiality.

CWE-862: Missing Authorization

Reaching this weakness in Get Custom Field Values < 4.0 takes a caller who can reach the endpoint. A missing authorization check means a function is reachable by anyone who can reach the endpoint, because the code never asks whether the caller is allowed to perform the action.

Any user who can reach the endpoint gets to run an action reserved for higher-privileged roles, from reading protected data to changing settings or content. For Get Custom Field Values the fix is 4.0: builds < 4.0 are affected, anything from 4.0 onward is not.

Remediation

Update to version 4.0, or a newer patched version

How does WordSec protect against this?

Because it turns on account access, WordSec's login security is the relevant layer: role-based two-factor, captcha and brute-force limits raise the cost of getting the account this needs. None of that substitutes for the fix: Get Custom Field Values 4.0 closes this, and updating the plugin is the step that ends it.

Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-24872 https://www.wordfence.com/threat-intel/vulnerabilities/id/8ff1ca68-7c71-4442-b27f-12743fc39b37 https://nvd.nist.gov/vuln/detail/CVE-2021-24872

Related records

Other vulnerabilities in Get Custom Field Values

CVSS Vector

6.5

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityNone
AvailabilityNone

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