The 6Storage Rentals plugin for WordPress is vulnerable to Authentication Bypass leading to Administrator Account Takeover in all versions up to, and including, 2.31.0. The vulnerability exists because the `six_storage_portal_registration()` AJAX handler — registered on `wp_ajax_six_storage_portal_plugin_registration` — performs no capability check and no nonce verification before writing the caller-supplied `six_storage_online_api_url` POST parameter to the site-wide option of the same name; the unauthenticated `six_storage_create_wp_user()` handler then redeems a transient seeded from that attacker-controlled URL's response and unconditionally calls `wp_set_current_user()` and `wp_set_auth_cookie()` with no ownership or credential verification. This makes it possible for authenticated attackers, with Subscriber-level access and above, to authenticate as any existing WordPress user — including any administrator whose email address is known or guessable — resulting in full site compromise. This issue represents an incomplete fix for a prior vulnerability: the 2.29.0 remediation moved the target email out of POST data into a server-side transient, but because any Subscriber can still overwrite the outbound API URL that populates that transient, the full authentication bypass chain remains exploitable in three AJAX requests.
Severity
CVSS 3.1
8.8 high
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.7% estimated probability of exploitation activity in the next 30 days; 54th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
CISA's assessment (SSVC)
Exploitation: none · Automatable: no · Technical impact: total, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
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