CVE-2015-5623

WordPress Core < 4.2.3 - Authorization Bypass

2015-07-23 00:00

Strategic Overview

Status: Patched in 3.7.9
Affected Core: WordPress 4.2
Affected Version: 3.7 – 4.2.2 · 7 branches
CVSS: 6.5Medium
Weakness type: CWE-862 · Missing Authorization
CVE: CVE-2015-5623

At a glance

CVE-2015-5623 is a medium-severity Missing Authorization vulnerability in the WordPress 4.2 WordPress release line, affecting 3.7 – 4.2.2 · 7 branches. It carries a CVSS score of 6.5 (reachable over the network; low attack complexity; high integrity impact). The issue is fixed in version 3.7.9; sites on affected versions should update now. Disclosed July 2015, reported by Netanel Rubin.

Vulnerability Overview

WordPress before 4.2.3 does not properly verify the edit_posts capability, which allows remote authenticated users to bypass intended access restrictions and create drafts by leveraging the Subscriber role, as demonstrated by a post-quickdraft-save action to wp-admin/post.php.

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 integrity.

CWE-862: Missing Authorization

Reaching this weakness in WordPress 4.2 3.7 – 4.2.2 · 7 branches 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 WordPress 4.2 the fix is 3.7.9: builds 3.7 – 4.2.2 · 7 branches are affected, anything from 3.7.9 onward is not.

Remediation

Update to one of the following versions, or a newer patched version: 3.7.9, 3.8.9, 3.9.7, 4.0.6, 4.1.6, 4.2.3

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 3.7.9 is the step that ends it.

Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2015-5623 https://www.wordfence.com/threat-intel/vulnerabilities/id/6b50656b-6cb4-4920-aa36-2634d4d41f5c https://nvd.nist.gov/vuln/detail/CVE-2015-5623

Related records

Same weakness class

Other vulnerabilities in WordPress 4.2

CVSS Vector

6.5

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeUnchanged
ConfidentialityNone
IntegrityHigh
AvailabilityNone

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