--- id: CVE-2026-103482 title: >- The Simple Newsletter Plugin – Noptin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'noptin_fields[] (e.g summary: >- The Simple Newsletter Plugin – Noptin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'noptin_fields[] (e.g. first_name)' parameter in all versions up to, and including, 4.3.10 due to ins… severity: medium cvss: 5.4 cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N' cwe: - CWE-79 published: '2026-10-10' updated: '2026-10-10' sourceUpdated: '2026-10-10T06:16:36.887' source: NVD sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-103482' references: - url: 'https://github.com/hizzle-co/noptin/compare/4.3.10...4.4.0' label: security@wordfence.com - url: >- https://plugins.trac.wordpress.org/browser/newsletter-optin-box/tags/4.3.10/build/Core/Dynamic_Content_Tags.php#L361 label: security@wordfence.com - url: >- https://plugins.trac.wordpress.org/browser/newsletter-optin-box/tags/4.3.10/build/Core/Dynamic_Content_Tags.php#L507 label: security@wordfence.com - url: >- https://plugins.trac.wordpress.org/browser/newsletter-optin-box/tags/4.3.10/build/Core/Dynamic_Content_Tags.php#L695 label: security@wordfence.com - url: >- https://plugins.trac.wordpress.org/browser/newsletter-optin-box/tags/4.3.10/build/Emails/Generate/Generator.php#L548 label: security@wordfence.com - url: >- https://plugins.trac.wordpress.org/browser/newsletter-optin-box/tags/4.3.10/build/Emails/Preview.php#L161 label: security@wordfence.com - url: >- https://plugins.trac.wordpress.org/browser/newsletter-optin-box/tags/4.3.10/build/Subscribers/Manage_Preferences.php#L255 label: security@wordfence.com - url: >- https://plugins.trac.wordpress.org/browser/newsletter-optin-box/tags/4.3.10/build/Subscribers/functions.php#L937 label: security@wordfence.com - url: >- https://plugins.trac.wordpress.org/browser/newsletter-optin-box/tags/4.3.10/vendor/hizzle/store/src/Prop.php#L626 label: security@wordfence.com - url: >- https://www.wordfence.com/threat-intel/vulnerabilities/id/e5f8afa3-f20c-4dfb-bcc6-2682f68723ca?source=cve label: security@wordfence.com tags: - nvd ingestedAt: '2026-10-10T06:24:42.856Z' --- ## Overview The Simple Newsletter Plugin – Noptin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'noptin_fields[] (e.g. first_name)' parameter in all versions up to, and including, 4.3.10 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 attack chain requires a published campaign post whose body contains a [[subscriber.*]] merge tag; the unauthenticated attacker first POSTs the entity-encoded payload to the public manage_preferences form (which issues its own nonce on the same page), then pivots execution by embedding their confirm_key in a campaign preview URL sent to a privileged user via social engineering. ## Remediation Refer to the linked advisories for vendor-supplied fixes and affected version ranges.