CVE-2026-15664
Quill Forms | Conversational Multi Step Forms, Surveys & quizzes <= 5.7.1 - Unauthenticated Stored Cross-Site Scripting via Multiple Choice 'Other' Value
- 7.2HighCVSS base score
- 0.53%Exploitation in 30 daysEPSS · top 55% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
The Quill Forms | Conversational Multi Step Forms, Surveys & quizzes plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Multiple Choice 'Other' Value in all versions up to, and including, 5.7.1 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. The injected script executes in the context of the WordPress admin results view, making administrators the primary target when reviewing submitted form entries.
Timeline
ID reserved
By Wordfence
- 2 months later
· 2 months later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| WordfenceCNA (assigner) | 3.1 | High7.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
| NVDNVD · Deferred | 3.1 | High7.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.53% · top 55% of all CVEs (11 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.2.
Affected products
mdmag · Quill Forms | Conversational Multi Step Forms, Surveys & quizzes
- affected ≤ 5.7.1
References
References14
- https://www.wordfence.com/threat-intel/vulnerabilities/id/1261881f-7a04-47fb-8176-6a9ac2088f8d?source=cve (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/quillforms/tags/5.6.1/includes/class-form-submission.php#L111 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/quillforms/tags/5.6.1/includes/class-form-submission.php#L194 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/quillforms/tags/5.6.1/includes/class-form-submission.php#L262 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/quillforms/tags/5.6.1/includes/abstracts/class-block-type.php#L402 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/quillforms/tags/5.7.0/includes/blocks/multiple-choice/class-multiple-choice-block.php#L199 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/quillforms/tags/5.7.0/includes/class-form-submission.php#L194 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/quillforms/tags/5.7.0/includes/class-form-submission.php#L262 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/quillforms/tags/5.7.0/includes/abstracts/class-block-type.php#L402 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/quillforms/tags/5.7.0/includes/class-form-submission.php#L111 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/quillforms/tags/5.7.0/includes/rest-api/controllers/v1/class-rest-entry-controller.php#L191 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/quillforms/tags/5.6.1/includes/blocks/multiple-choice/class-multiple-choice-block.php#L199 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/quillforms/tags/5.6.1/includes/rest-api/controllers/v1/class-rest-entry-controller.php#L191 (opens in a new tab)
- https://plugins.trac.wordpress.org/changeset?reponame=&old=3663009%40quillforms&new=3663009%40quillforms (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-83574 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-15664)Record last updated .