{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-15341",
        "assignerOrgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
        "state": "PUBLISHED",
        "assignerShortName": "Wordfence",
        "dateReserved": "2026-07-09T20:00:20.994Z",
        "datePublished": "2026-08-15T02:26:17.894Z",
        "dateUpdated": "2026-08-15T02:26:17.894Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
                "shortName": "Wordfence",
                "dateUpdated": "2026-08-15T02:26:17.894Z"
            },
            "affected": [
                {
                    "vendor": "rafasashi",
                    "product": "User Session Synchronizer",
                    "versions": [
                        {
                            "version": "0",
                            "status": "affected",
                            "lessThanOrEqual": "1.4.0",
                            "versionType": "semver"
                        }
                    ],
                    "defaultStatus": "unaffected"
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "The User Session Synchronizer plugin for WordPress is vulnerable to Authentication Bypass leading to Account Takeover in all versions up to, and including, 1.4.0. The `synchronize_session()` function, hooked on `init` and therefore executed on every request, performs no nonce, capability, or shared-secret validation against the attacker-supplied `ussync-key`, `ussync-token`, and `ussync-ref` parameters; when `ussync-key` references an unregistered slot, `get_option()` returns `false` for both the secret key and the domain list, causing the AES-256-CBC encryption key to degrade to the fully predictable `md5('')` and the referer allowlist to collapse to an empty-string match, while the AES IV is unconditionally hard-coded as `md5('another-secret')`. This makes it possible for unauthenticated attackers to supply a crafted request encrypting any known or guessable user email address in the `ussync-ref` parameter, causing the handler to call `wp_set_auth_cookie()` for the matched user and granting full authentication as that user — including administrators — with no prior knowledge of site secrets."
                }
            ],
            "title": "User Session Synchronizer <= 1.4.0 - Unauthenticated Authentication Bypass to Account Takeover via 'ussync-key', 'ussync-token', and 'ussync-ref' Parameters",
            "references": [
                {
                    "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/cbc32e6d-47c5-4050-ba77-5a54203fe56a?source=cve"
                },
                {
                    "url": "https://plugins.trac.wordpress.org/browser/user-session-synchronizer/tags/1.4.0/includes/class-user-session-synchronizer.php#L422"
                },
                {
                    "url": "https://plugins.trac.wordpress.org/browser/user-session-synchronizer/tags/1.4.0/includes/class-user-session-synchronizer.php#L117"
                },
                {
                    "url": "https://plugins.trac.wordpress.org/browser/user-session-synchronizer/tags/1.4.0/includes/class-user-session-synchronizer.php#L286"
                },
                {
                    "url": "https://plugins.trac.wordpress.org/browser/user-session-synchronizer/tags/1.4.0/includes/class-user-session-synchronizer.php#L310"
                },
                {
                    "url": "https://plugins.trac.wordpress.org/browser/user-session-synchronizer/tags/1.4.0/includes/class-user-session-synchronizer.php#L631"
                },
                {
                    "url": "https://plugins.trac.wordpress.org/browser/user-session-synchronizer/tags/1.4.0/includes/class-user-session-synchronizer.php#L598"
                }
            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "description": "CWE-287 Improper Authentication",
                            "cweId": "CWE-287",
                            "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": "Afan"
                },
                {
                    "lang": "en",
                    "type": "finder",
                    "value": "moonge"
                }
            ],
            "timeline": [
                {
                    "time": "2026-08-14T14:02:18.000Z",
                    "lang": "en",
                    "value": "Disclosed"
                }
            ]
        }
    }
}