XSS in Expresstech Quiz And Survey Master (Qsm) – Maker &

CVE-2026-11780

The Quiz and Survey Master (QSM) – Easy Quiz and Survey Maker plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'question_title' parameter in all versions up to, and including, 11.2.1 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.004 (33.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 34th percentile — 33.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-11780: held from 0.003 to 0.004.

EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-11780?
CVE-2026-11780 is a medium-severity vulnerability in Expresstech Quiz And Survey Master (Qsm) – Maker &, classified under Cross-site Scripting. CVSS score: 6.4/10. Published 2026-08-16.
How severe is CVE-2026-11780?
Medium severity. CVSS v3 base score is 6.4 out of 10.