{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-109515",
        "assignerOrgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
        "state": "PUBLISHED",
        "assignerShortName": "Wordfence",
        "dateReserved": "2026-10-12T18:05:34.654Z",
        "datePublished": "2026-10-16T04:27:01.480Z",
        "dateUpdated": "2026-10-16T15:09:39.848Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
                "shortName": "Wordfence",
                "dateUpdated": "2026-10-16T04:27:01.480Z"
            },
            "affected": [
                {
                    "vendor": "properfraction",
                    "product": "MailOptin – Popup, Optin Forms & Email Newsletters for Mailchimp, HubSpot, AWeber Etc.",
                    "versions": [
                        {
                            "version": "0",
                            "status": "affected",
                            "lessThanOrEqual": "1.2.78.6",
                            "versionType": "semver"
                        }
                    ],
                    "defaultStatus": "unaffected"
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "The MailOptin – Popup, Optin Forms & Email Newsletters for Mailchimp, HubSpot, AWeber Etc. plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 1.2.78.6 This is due to the `subscribe_to_email_list` endpoint accepting an attacker-supplied `optin_data[form_custom_field_mappings]` parameter without any allow-list validation on destination keys, allowing the attacker-controlled mapping to override the administrator's saved mapping and pass arbitrary `wp_users` column names — including `ID` and `user_pass` — directly into `wp_insert_user()` via the `subscribe()` function. This makes it possible for unauthenticated attackers to force `wp_insert_user()` into UPDATE mode on any existing account by supplying a target user's numeric `ID`, overwrite that account's password with a pre-hashed value of their choosing, and thereby take over any WordPress user account — including administrators — leading to full site compromise. Exploitation requires that a WordPress User Registration opt-in form is published somewhere on the site, though the form's UUID is visible in page source and no authentication, nonce, or capability check is required to reach the vulnerable endpoint."
                }
            ],
            "title": "MailOptin <= 1.2.78.6 - Unauthenticated Privilege Escalation to 'form_custom_field_mappings' Parameter",
            "references": [
                {
                    "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/96111116-6b6f-42fc-98d8-6f5c27dc3c1c?source=cve"
                },
                {
                    "url": "https://plugins.trac.wordpress.org/browser/mailoptin/tags/1.2.78.5/src/connections/WordPressUserRegistrationConnect/Subscription.php#L68"
                },
                {
                    "url": "https://plugins.trac.wordpress.org/browser/mailoptin/tags/1.2.78.5/src/core/src/Connections/AbstractConnect.php#L84"
                },
                {
                    "url": "https://plugins.trac.wordpress.org/browser/mailoptin/tags/1.2.78.5/src/core/src/AjaxHandler.php#L699"
                },
                {
                    "url": "https://plugins.trac.wordpress.org/changeset?reponame=&new=3744644%40mailoptin%2Ftrunk&old=3738326%40mailoptin%2Ftrunk#file4"
                },
                {
                    "url": "https://plugins.trac.wordpress.org/changeset/3744644/mailoptin/trunk/src/connections/WordPressUserRegistrationConnect/Subscription.php"
                }
            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "description": "CWE-269 Improper Privilege Management",
                            "cweId": "CWE-269",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                        "baseScore": 9.8,
                        "baseSeverity": "CRITICAL"
                    }
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "type": "finder",
                    "value": "Kuba"
                }
            ],
            "timeline": [
                {
                    "time": "2026-10-12T18:20:28.000Z",
                    "lang": "en",
                    "value": "Vendor Notified"
                },
                {
                    "time": "2026-10-15T16:09:03.000Z",
                    "lang": "en",
                    "value": "Disclosed"
                }
            ]
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "id": "CVE-2026-109515",
                                "role": "CISA Coordinator",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "yes"
                                    },
                                    {
                                        "Technical Impact": "total"
                                    }
                                ],
                                "version": "2.0.3",
                                "timestamp": "2026-10-16T14:56:30.538755Z"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-10-16T15:09:39.848Z"
                }
            }
        ]
    }
}