CVE-2026-96558: expresstech quiz and survey master (qsm) – quiz maker & survey maker Cross-site Scripting

Vulnerability summary

CVE-2026-96558 is a high (CVSS 7.2) Cross-site Scripting vulnerability in expresstech quiz and survey master (qsm) – quiz maker & survey maker. EPSS estimates a 0.24% chance of exploitation in the next 30 days, higher than 14.2% of scored vulnerabilities. Fixed in 11.2.7.

Timeline

1. 10-10-2026
   PublishedVulnerability first disclosed.
2. 11-10-2026
   Last modifiedVulnerability information updated.

Description

The Quiz and Survey Master (QSM) – Quiz Maker & Survey Maker plugin for WordPress is vulnerable to Stored DOM-Based Cross-Site Scripting via the 'qsm_hidden_questions' parameter in all versions up to, and including, 11.2.6 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This requires the attacker to force the mlw_results INSERT to fail by submitting an over-length or duplicate qsm_unique_key value, which triggers the audit trail code branch that writes the unescaped payload to wp_mlw_qm_audit_trail.form_data.

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.