CVE-2017-9065

WordPress Core < 4.7.5 - Authorization Bypass Allowing Post Meta Updates

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: 5.4Medium
Weakness type: CWE-285 · Improper Authorization
CVE: CVE-2017-9065

At a glance

CVE-2017-9065 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 5.4 (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 Ben Bidner.

Vulnerability Overview

In WordPress before 4.7.5, there is a lack of capability checks for post meta data 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-2017-9065 https://www.wordfence.com/threat-intel/vulnerabilities/id/801d6f21-1f52-48d4-9f8e-5c971dd037f7 https://nvd.nist.gov/vuln/detail/CVE-2017-9065

Related records

Same weakness class

Other vulnerabilities in WordPress 4.7

CVSS Vector

5.4

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

Base

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

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