CVE-2017-9062

WordPress Core < 4.7.5 - Mishandling Post Meta Values via XML-RPC

2017-05-16 00:00

Strategic Overview

Status: Patched in 3.7.21
Affected Core: WordPress 4.7
Affected Version: 3.7 – 4.7.4 · 12 branches
CVSS: 6.3Medium
Weakness type: CWE-285 · Improper Authorization
CVE: CVE-2017-9062

At a glance

CVE-2017-9062 is a medium-severity Improper Authorization vulnerability in the WordPress 4.7 WordPress release line, affecting 3.7 – 4.7.4 · 12 branches. It carries a CVSS score of 6.3 (reachable over the network; low attack complexity). The issue is fixed in version 3.7.21; sites on affected versions should update now. Disclosed May 2017, reported by Sam Thomas.

Vulnerability Overview

In WordPress before 4.7.5, there is improper handling of post meta data values in the XML-RPC API.

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.

CWE-285: Improper Authorization

Reaching this weakness in WordPress 4.7 3.7 – 4.7.4 · 12 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 4.7 the fix is 3.7.21: builds 3.7 – 4.7.4 · 12 branches are affected, anything from 3.7.21 onward is not.

Remediation

Update to one of the following versions, or a newer patched version: 3.7.21, 3.8.21, 3.9.19, 4.0.18, 4.1.18, 4.2.15, 4.3.11, 4.4.10, 4.5.9, 4.6.6, 4.7.5

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 3.7.21 is the step that ends it.

Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2017-9062 https://www.wordfence.com/threat-intel/vulnerabilities/id/f7d66176-73a8-4076-8ae0-1f1fd8260f8e https://nvd.nist.gov/vuln/detail/CVE-2017-9062

Related records

Same weakness class

Other vulnerabilities in WordPress 4.7

CVSS Vector

6.3

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeUnchanged
ConfidentialityLow
IntegrityLow
AvailabilityLow

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