CVE-2026-15664 json
Quill Forms | Conversational Multi Step Forms, Surveys & quizzes <= 5.7.1 - Unauthenticated Stored Cross-Site Scripting via Multiple Choice 'Other' Value
published last mo. modified last mo. also EUVD-2026-83574
- cvss
- 7.2
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 44%
- public exploits
- 0
- none known
Summary
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.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.53% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
Affected products
- mdmag Quill Forms | Conversational Multi Step Forms, Surveys & quizzes
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/1261881f-7a04-47fb-8176-6a9ac2088f8d?source=cve
- plugins.trac.wordpress.org /browser/quillforms/tags/5.6.1/includes/class-form-submission.php#L111
- plugins.trac.wordpress.org /browser/quillforms/tags/5.6.1/includes/class-form-submission.php#L194
- plugins.trac.wordpress.org /browser/quillforms/tags/5.6.1/includes/class-form-submission.php#L262
- plugins.trac.wordpress.org /browser/quillforms/tags/5.6.1/includes/abstracts/class-block-type.php#L402
- plugins.trac.wordpress.org /browser/quillforms/tags/5.7.0/includes/blocks/multiple-choice/class-multiple-choice-block.php#L199
- plugins.trac.wordpress.org /browser/quillforms/tags/5.7.0/includes/class-form-submission.php#L194
- plugins.trac.wordpress.org /browser/quillforms/tags/5.7.0/includes/class-form-submission.php#L262
- plugins.trac.wordpress.org /browser/quillforms/tags/5.7.0/includes/abstracts/class-block-type.php#L402
- plugins.trac.wordpress.org /browser/quillforms/tags/5.7.0/includes/class-form-submission.php#L111
- plugins.trac.wordpress.org /browser/quillforms/tags/5.7.0/includes/rest-api/controllers/v1/class-rest-entry-controller.php#L191
- plugins.trac.wordpress.org /browser/quillforms/tags/5.6.1/includes/blocks/multiple-choice/class-multiple-choice-block.php#L199
- plugins.trac.wordpress.org /browser/quillforms/tags/5.6.1/includes/rest-api/controllers/v1/class-rest-entry-controller.php#L191
- plugins.trac.wordpress.org /changeset?reponame=&old=3663009%40quillforms&new=3663009%40quillforms
Sources
- CVE List CVE-2026-15664
- NVD CVE-2026-15664
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.