CVE-2026-6456

CVE-2026-6456 is a high-severity vulnerability with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Description

The Account Switcher plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 1.0.2. This is due to the `rememberLogin` REST API endpoint using a loose comparison (`!=` instead of `!==`) for secret validation at `app/RestAPI.php:111`, combined with no validation that the secret is non-empty. When a target user has never used the "Remember me" feature, their `asSecret` user meta does not exist, causing `get_user_meta()` to return an empty string. An attacker can send an empty `secret` parameter, which passes the comparison (`'' != ''` is `false`), and the endpoint then calls `wp_set_auth_cookie()` for the target user. Additionally, all REST routes use `permission_callback => '__return_true'` with no capability checks. This makes it possible for authenticated attackers, with Subscriber-level access and above, to switch to any user account including Administrator, ultimately granting themselves full administrative privileges.

Frequently asked questions

What is CVE-2026-6456?
The Account Switcher plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 1.0.2. This is due to the `rememberLogin` REST API endpoint using a loose comparison (`!=` instead of `!==`) for secret validation at `app/RestAPI.php:111`, combined with no validation that the secret is non-empty. When a target user has never used the "Remember me" feature, their `asSecret` user meta does not exist, causing `get_user_meta()` to return an empty string. An attacker can send an empty `secret` parameter, which passes the comparison (`'' != ''` is `false`), and the endpoint then calls `wp_set_auth_cookie()` for the target user. Additionally, all REST routes use `permission_callback => '__return_true'` with no capability checks. This makes it possible for authenticated attackers, with Subscriber-level access and above, to switch to any user account including Administrator, ultimately granting themselves full administrative privileges.
How severe is CVE-2026-6456?
CVE-2026-6456 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-6456 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-6456?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-6456 have an EU (EUVD) identifier?
Yes. CVE-2026-6456 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31026.
When was CVE-2026-6456 published?
CVE-2026-6456 was published on 2026-05-20 and last updated on 2026-06-17.

References

Other CWE-287 (Improper Authentication) vulnerabilities

Browse all CWE-287 (Improper Authentication) vulnerabilities →