CVE-2026-62140

Quiz and Survey Master (QSM) – Quiz Maker & Survey Maker <= 11.2.5 - Unauthenticated Insecure Direct Object Reference

2026-09-10 00:00
Adam Kahlon

Strategic Overview

Status
Patched in 11.2.6
Affected Plugin
Quiz and Survey Master (QSM) – Quiz Maker & Survey Maker
Affected Version
<= 11.2.5
CVSS
5.3Medium
Weakness type
CWE-639 · Authorization Bypass Through User-Controlled Key
CVE
CVE-2026-62140
View all Quiz and Survey Master (QSM) – Quiz Maker & Survey Maker vulnerabilities

At a glance

CVE-2026-62140 is a medium-severity Authorization Bypass Through User-Controlled Key vulnerability in the Quiz and Survey Master (QSM) WordPress plugin, affecting versions <= 11.2.5. It carries a CVSS score of 5.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 11.2.6; sites on affected versions should update now. Disclosed September 2026, reported by Adam Kahlon.

Vulnerability Overview

The Quiz and Survey Master (QSM) – Quiz Maker & Survey Maker plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 11.2.5. This is due to missing validation on a user controlled key. This makes it possible for unauthenticated attackers 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 privileges on the target site, and no interaction from a victim user.

CWE-639: Authorization Bypass Through User-Controlled Key

Reaching this weakness in Quiz and Survey Master (QSM) <= 11.2.5 takes no account at all. Authorization bypass through a user-controlled key, often called insecure direct object reference, means the application looks up a record by an identifier from the request without checking that the caller owns it.

Changing a number in the request is enough to read or modify other users' records, which on commerce and membership sites means customer data. For Quiz and Survey Master (QSM) the fix is 11.2.6: builds <= 11.2.5 are affected, anything from 11.2.6 onward is not.

Remediation

Update to version 11.2.6, or a newer patched version

How does WordSec protect against this?

This one needs no account at all, which puts it outside what login hardening can reach; WordSec's login security narrows the account-level paths around it, and the firewall is what inspects the request itself. None of that substitutes for the fix: Quiz and Survey Master (QSM) 11.2.6 closes this, and updating the plugin is the step that ends it.

  • Login Security
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-62140https://www.wordfence.com/threat-intel/vulnerabilities/id/3d6763a3-6773-41fe-b7fd-f21c34963bd8https://nvd.nist.gov/vuln/detail/CVE-2026-62140

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C