{
 "id": "WPSEC-2026-0461",
 "url": "https://wpsec.com/vuln/WPSEC-2026-0461/",
 "json_url": "https://wpsec.com/vuln/WPSEC-2026-0461/advisory.json",
 "markdown_url": "https://wpsec.com/vuln/WPSEC-2026-0461/index.md",
 "title": "MailOptin – Popup, Optin Forms & Email Newsletters for Mailchimp, HubSpot, AWeber Etc. <= 1.2.78.4 - Unauthenticated Admin Email Flooding via subscribe_to_email_list",
 "description": "The MailOptin plugin for WordPress is vulnerable to admin email flooding in all versions up to, and including, 1.2.78.4. The public subscribe_to_email_list action does not check that the submitted opt-in campaign exists and has no rate limiting, and the plugin emails the site administrator an error notification, without any throttling, each time a subscription fails because no email provider or list is set for the campaign. This makes it possible for unauthenticated attackers to send repeated subscription requests naming a non-existent campaign, each of which sends an error email to the site administrator and stores a junk lead record.",
 "plugin": {
  "slug": "mailoptin",
  "name": "MailOptin – Popup, Optin Forms & Email Newsletters for Mailchimp, HubSpot, AWeber Etc.",
  "full_name": "MailOptin – Popup, Optin Forms & Email Newsletters for Mailchimp, HubSpot, AWeber Etc.",
  "wordpress_org": "https://wordpress.org/plugins/mailoptin/",
  "advisories_url": "https://wpsec.com/vuln/plugin/mailoptin/",
  "attacksurface": "https://attacksurface.wpsec.com/plugin/mailoptin"
 },
 "type": "UNKNOWN",
 "cwe": [
  "CWE-770"
 ],
 "cve": [],
 "cvss": {
  "version": "3.1",
  "score": 5.3,
  "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
  "severity": "Medium"
 },
 "affected": {
  "ranges": [
   {
    "from": null,
    "from_inclusive": true,
    "to": "1.2.78.5",
    "to_inclusive": false
   }
  ],
  "text": [
   "all versions before 1.2.78.5"
  ]
 },
 "introduced_in": null,
 "fixed_in": "1.2.78.5",
 "remediation": "Update to 1.2.78.5 or later.",
 "fix_released": "2026-10-05T12:46:34+00:00",
 "published": "2026-10-06T17:44:03+00:00",
 "updated": "2026-10-06T16:46:17.776816+00:00",
 "also_published_as": null,
 "references": [
  "https://wpsec.com/vuln/WPSEC-2026-0461/",
  "https://plugins.svn.wordpress.org/mailoptin/tags/1.2.78.5/",
  "https://wordpress.org/plugins/mailoptin/"
 ],
 "attacksurface_url": "https://attacksurface.wpsec.com/plugin/mailoptin",
 "source": "WPSec",
 "license": {
  "name": "CC BY 4.0",
  "url": "https://creativecommons.org/licenses/by/4.0/"
 },
 "usage": {
  "plugin": "Medium",
  "affected_versions": "Medium",
  "as_of": "2026-10-06"
 }
}