AMP for WP <= 0.9.97.19 - Missing Authorization

2018-10-20 00:00
Sybre Waaijer

Strategic Overview

Status
Patched in 0.9.97.20
Affected Plugin
AMP for WP – Accelerated Mobile Pages
Affected Version
<= 0.9.97.19
CVSS
6.3Medium
Weakness type
CWE-862 · Missing Authorization
CVE
CVE pending
View all AMP for WP – Accelerated Mobile Pages vulnerabilities

At a glance

This record tracks a medium-severity Missing Authorization vulnerability in the AMP for WP WordPress plugin, affecting versions <= 0.9.97.19. It carries a CVSS score of 6.3 (reachable over the network; low attack complexity). The root cause is a missing authorization check on a reachable function. The issue is fixed in version 0.9.97.20; sites on affected versions should update now. Disclosed October 2018, reported by Sybre Waaijer.

Vulnerability Overview

TheAMP for WP plugin for WordPress is vulnerable to authorization bypass due to a missing capability check on the ampforwp_save_steps_data AJAX hook in versions up to, and including, 0.9.97.19. This makes it possible for authenticated attackers to make otherwise privilege locked administrative changes to the vulnerable website and create admin accounts.

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-862: Missing Authorization

Reaching this weakness in AMP for WP <= 0.9.97.19 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 AMP for WP the fix is 0.9.97.20: builds <= 0.9.97.19 are affected, anything from 0.9.97.20 onward is not.

Remediation

Update to version 0.9.97.20, 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: AMP for WP 0.9.97.20 closes this, and updating the plugin is the step that ends it.

  • Login Security
  • Alerts

External References

https://www.wordfence.com/threat-intel/vulnerabilities/id/9ea2964f-9e3a-450b-9724-5a520c73d306

Related records

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