Advanced Twenty Seventeen <= 1.3.1 - Missing Authorization
Strategic Overview
- Status
- Unpatched
- Affected Plugin
- Advanced Twenty Seventeen
- Affected Version
<= 1.3.1- CVSS
- 4.3Medium
- Weakness type
- CWE-862 · Missing Authorization
- CVE
CVE-2026-107887
At a glance
CVE-2026-107887 is a medium-severity Missing Authorization vulnerability in the Advanced Twenty Seventeen WordPress plugin, affecting versions <= 1.3.1. It carries a CVSS score of 4.3 (reachable over the network; low attack complexity). The root cause is a missing authorization check on a reachable function. No fixed release has been reported yet; treat installations running this software as exposed. Disclosed October 2026, reported by Seongwon Lee.
Vulnerability Overview
The Advanced Twenty Seventeen plugin for WordPress is vulnerable to unauthorized access in all versions up to, and including, 1.3.1. This is due to a missing capability check on a function. This makes it possible for authenticated attackers, with subscriber-level access and above, to perform an unauthorized action.
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 Advanced Twenty Seventeen <= 1.3.1 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. No fixed build of this plugin is recorded for Advanced Twenty Seventeen yet, so installs running <= 1.3.1 stay exposed until the vendor ships one.
Remediation
No known patch available. Please review the vulnerability's details in depth and employ mitigations based on your organization's risk tolerance. It may be best to uninstall the affected software and find a replacement.
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. No patched version is recorded yet, which is the case where a filtering layer matters most, because there is nothing to update to.
- Login Security
- Alerts
External References
Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C