CVE-2026-7459: Simple History WordPress Plugin Account Takeover Vulnerability

CVE-2026-7459 affects the Simple History – Track, Log, and Audit WordPress Changes plugin for WordPress, versions up to and including 5.26.0. An authenticated subscriber-level user can exploit the vulnerability to read the full context of Simple History events, including password reset emails, via the event reaction endpoints (react_to_event() / unreact_to_event()). The vulnerability stems from insufficient permission checks in the get_items_permissions_check() function, which only verifies the user is logged in, failing to enforce logger-specific capability checks. Successful exploitation allows an attacker to extract password reset keys for other users, including administrators, and ultimately take over their accounts. Note that the experimental features option (simple_history_experimental_features_enabled) must be enabled for the vulnerability to be exploitable; this option is not enabled by default.

Attack Chain

1. The attacker obtains a subscriber-level account on the target WordPress site.
2. The administrator enables the experimental features option within the Simple History plugin.
3. The attacker navigates to the WordPress lost password form and requests a password reset for the administrator account. This triggers a user_requested_password_reset_link event in the Simple History log.
4. The attacker sends a POST request to /wp-json/simple-history/v1/events/<id>/react with the _fields=context parameter, attempting to brute-force the event ID.
5. If the correct event ID for the password reset event is found, the server responds with the full event context, including the password reset email body within the context.message field.
6. The attacker extracts the password reset key from the context.message field.
7. The attacker uses the extracted reset key to complete the password reset process for the administrator account.
8. The attacker logs in to the WordPress site with the compromised administrator credentials, achieving full account takeover.

Impact

Successful exploitation of CVE-2026-7459 allows an attacker to gain complete control over a WordPress website by compromising an administrator account. This can lead to defacement of the website, installation of malicious plugins or themes, data theft, and further compromise of the underlying server. Since exploitation requires the experimental features option to be enabled, the number of affected sites might be lower than sites with the plugin installed.

Recommendation

• Upgrade to a patched version of the Simple History plugin (later than 5.26.0) to remediate CVE-2026-7459.
• Disable the experimental features option (simple_history_experimental_features_enabled) in the Simple History plugin settings as a temporary mitigation if upgrading is not immediately possible.
• Deploy the Sigma rule Detect Simple History Password Reset Email Access to your SIEM and tune for your environment to detect potential exploitation attempts.
• Deploy the Sigma rule Detect Simple History Event Context Access to detect unauthorized access to event contexts in Simple History logs.