CVE-2026-1748: 
WordPress vulnerability analysis and mitigation

CVE-2026-1748 is a Missing Authorization vulnerability in the Invoct – PDF Invoices & Billing for WooCommerce plugin for WordPress. It affects all versions up to and including 1.6, allowing authenticated attackers with Subscriber-level access or above to access sensitive data without proper authorization checks. The vulnerability was published on February 11, 2026, and carries a CVSS v3.1 base score of 4.3 (Medium) (Red Hat CVE, Feedly).

The root cause is a missing capability check (CWE-862) on multiple functions within the Invoct plugin, meaning the plugin fails to verify whether the requesting user has sufficient privileges before executing sensitive operations. An authenticated attacker with at minimum Subscriber-level access can send crafted network requests to these unprotected endpoints to retrieve invoice client data, invoice items, and a list of WordPress users along with their email addresses. No complex preconditions are required beyond having a valid low-privilege account on the target WordPress site (Red Hat CVE, Feedly).

Successful exploitation results in unauthorized disclosure of sensitive business and personal data, including invoice client records, invoice line items, and WordPress user email addresses. The confidentiality impact is limited in scope (no integrity or availability impact), but the exposed user email list could facilitate phishing campaigns or credential stuffing attacks against site users. The vulnerability does not allow privilege escalation or remote code execution on its own (Red Hat CVE).

No public proof-of-concept exploit code or active in-the-wild exploitation has been reported for CVE-2026-1748. The EPSS score is approximately 0.028%, indicating a low probability of exploitation in the near term. The vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog. Exploitation requires a valid authenticated account (Subscriber level or above), which limits the attack surface compared to unauthenticated vulnerabilities (Feedly).

1. Reconnaissance: Identify WordPress sites running the Invoct – PDF Invoices & Billing for WooCommerce plugin version 1.6 or earlier using tools like WPScan or by inspecting plugin directories.
2. Obtain low-privilege account: Register or obtain a Subscriber-level (or higher) account on the target WordPress site, which may be possible if user registration is open.
3. Authenticate: Log in to the WordPress site with the low-privilege account to obtain a valid session cookie or nonce.
4. Call unprotected endpoints: Send authenticated HTTP requests to the plugin's unprotected AJAX or REST API endpoints (those lacking capability checks) to retrieve invoice client data, invoice items, or the WordPress user list with emails.
5. Exfiltrate data: Collect the returned sensitive data (client records, invoice details, user emails) for further use such as phishing or business intelligence gathering (Red Hat CVE, Feedly).

• Network: Unusual or repeated authenticated HTTP requests (POST/GET) to WordPress AJAX endpoints (/wp-admin/admin-ajax.php) or REST API routes associated with the Invoct plugin from low-privilege user accounts.
• Logs: WordPress access logs showing Subscriber-level users accessing invoice-related endpoints in high frequency or at unusual hours; unexpected queries for user lists or invoice data in server logs.
• Application: Unexpected access to invoice client or user data by accounts that should not require such access; audit log entries (if enabled via a plugin) showing Subscriber-level users triggering invoice or user retrieval actions.

Users should update the Invoct – PDF Invoices & Billing for WooCommerce plugin to a version beyond 1.6 that includes the capability check fix. Until a patch is applied, site administrators can mitigate risk by disabling open user registration to prevent untrusted parties from obtaining Subscriber-level accounts, and by reviewing existing low-privilege accounts for legitimacy. Monitoring WordPress audit logs for unusual access patterns to invoice-related endpoints is also recommended (Red Hat CVE, Feedly).