{"cve":"CVE-2026-83628","nvd":{"published":"2026-09-05T06:17:10.230","modified":"2026-09-08T13:12:58.310","status":"Deferred","description":"The Theme My Login plugin for WordPress is vulnerable to Missing Authorization in versions up to, and including, 7.1.15 on Multisite installations. This is due to the `tml_ms_signup_handler()` function's `gimmeanotherblog` branch failing to enforce the network's `active_signup` registration policy, checking only `is_user_logged_in()` while sibling branches such as `validate-blog-signup` apply the full policy gate. This makes it possible for authenticated attackers, with Subscriber-level access and above, to directly POST `stage=gimmeanotherblog` to Theme My Login's signup route, bypassing the configured registration policy entirely — even when it is set to `none` or `user` — which causes `wpmu_create_blog()` to execute with the attacker's user ID, after which WordPress core assigns the Administrator role on the newly created subsite via `add_user_to_blog()`. The privilege gain is scoped to the newly created subsite only; the attacker's account retains Subscriber-level access on the main site and does not obtain Super Admin or network-level capabilities such as `manage_network` or `manage_sites`.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","score":4.3},"cwes":["CWE-862"],"references":["https://plugins.trac.wordpress.org/browser/theme-my-login/tags/7.1.15/includes/ms-functions.php#L580","https://plugins.trac.wordpress.org/browser/theme-my-login/tags/7.1.15/includes/ms-functions.php#L661","https://plugins.trac.wordpress.org/browser/theme-my-login/tags/7.1.15/includes/ms-functions.php#L708","https://plugins.trac.wordpress.org/changeset/3669721/theme-my-login/trunk/includes/ms-functions.php","https://plugins.trac.wordpress.org/changeset?old_path=%2Ftheme-my-login/tags/7.1.15&new_path=%2Ftheme-my-login/tags/7.2.0"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:52:03.409947763+00:00"},"epss":{"cve":"CVE-2026-83628","score":0.00394,"percentile":0.33611,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}