CVE-2019-17671

WordPress Core < 5.2.4 - Authorization Bypass

2019-10-14 00:00

Strategic Overview

Status: Patched in 3.7.31
Affected Core: WordPress 5.2
Affected Version: 3.7 – 5.2.3 · 17 branches
CVSS: 5.3Medium
Weakness type: CWE-285 · Improper Authorization
CVE: CVE-2019-17671

At a glance

CVE-2019-17671 is a medium-severity Improper Authorization vulnerability in the WordPress 5.2 WordPress release line, affecting 3.7 – 5.2.3 · 17 branches. 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 3.7.31; sites on affected versions should update now. Disclosed October 2019, reported by J.D. Grimes.

Vulnerability Overview

In WordPress before 5.2.4, unauthenticated viewing of certain content is possible because the static query property is mishandled.

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-285: Improper Authorization

Reaching this weakness in WordPress 5.2 3.7 – 5.2.3 · 17 branches takes a caller who can reach the endpoint. Improper authorization means a permission check exists but does not cover the case being exercised, so a caller who is allowed to do one thing is allowed to do a neighbouring thing as well.

A lower-privileged account performs an action reserved for a higher one, which on a multi-author or membership site means an ordinary user reaching administrative behaviour. For WordPress 5.2 the fix is 3.7.31: builds 3.7 – 5.2.3 · 17 branches are affected, anything from 3.7.31 onward is not.

Remediation

Update to one of the following versions, or a newer patched version: 3.7.31, 3.8.31, 3.9.29, 4.0.28, 4.1.28, 4.2.25, 4.3.21, 4.4.20, 4.5.19, 4.6.16, 4.7.15, 4.8.11, 4.9.12, 5.0.7, 5.1.3, 5.2.4

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: updating to 3.7.31 is the step that ends it.

Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2019-17671 https://www.wordfence.com/threat-intel/vulnerabilities/id/6cc6d71c-fb19-4142-a8be-4175afc1713c https://nvd.nist.gov/vuln/detail/CVE-2019-17671

Related records

Same weakness class

Other vulnerabilities in WordPress 5.2

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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