CVE-2025-48161: YaySMTP Plugin SQL Injection Vulnerability

CVE-2025-48161 Overview

CVE-2025-48161 is a SQL Injection vulnerability in the YayCommerce YaySMTP plugin (smtp-sendinblue) for WordPress. The flaw stems from improper neutralization of special elements used in an SQL command [CWE-89]. Authenticated attackers with high privileges can inject arbitrary SQL statements through vulnerable input parameters. The issue affects all versions of YaySMTP up to and including version 1.3. Successful exploitation can expose sensitive database contents and affect the integrity of WordPress installations using the plugin.

Critical Impact
Authenticated attackers can execute arbitrary SQL queries against the WordPress database, leading to disclosure of confidential data stored in the database and potential service disruption.

Affected Products

YayCommerce YaySMTP plugin (smtp-sendinblue) for WordPress
All versions from initial release through 1.3
WordPress sites using YaySMTP for transactional email delivery

Discovery Timeline

2025-07-16 - CVE-2025-48161 published to NVD
2026-04-23 - Last updated in NVD database

Technical Details for CVE-2025-48161

Vulnerability Analysis

The vulnerability is classified as a SQL Injection flaw under [CWE-89]. YaySMTP fails to sanitize user-supplied input before incorporating it into SQL queries. An attacker with administrative or comparable privileges can craft malicious input that the plugin passes directly to the database engine. The scope is marked as changed, meaning a successful attack can affect components beyond the vulnerable plugin, including data in other WordPress tables on the same database.

Root Cause

The root cause is the absence of proper input sanitization and parameterized queries within the YaySMTP plugin code. User-controlled values are concatenated into SQL statements without escaping or prepared statement binding. This violates secure coding patterns recommended by the WordPress development standards, which require use of $wpdb->prepare() for all queries that include variable input.

Attack Vector

The attack is delivered over the network against the WordPress admin interface exposed by the plugin. The attacker must hold elevated privileges to reach the vulnerable functionality. Once authenticated, the attacker submits crafted parameters containing SQL metacharacters that break out of the intended query context. The injected payload then executes against the WordPress database with the privileges of the database user configured for the site.

For verified technical details and proof-of-concept information, refer to the Patchstack SQL Injection Advisory.

Detection Methods for CVE-2025-48161

Indicators of Compromise

Unexpected SQL syntax fragments such as UNION SELECT, OR 1=1, or -- appearing in WordPress access logs targeting YaySMTP endpoints
Database errors in PHP logs referencing YaySMTP plugin files
Unusual outbound queries or large result set retrievals originating from the WordPress database user
Administrative accounts performing requests to plugin admin pages at atypical times

Detection Strategies

Inspect web server access logs for suspicious query strings sent to YaySMTP admin endpoints under /wp-admin/
Enable WordPress debug logging and monitor wp-content/debug.log for wpdb query errors referencing the plugin
Deploy a web application firewall with rules tuned to flag SQL injection signatures against WordPress admin paths
Compare the installed YaySMTP plugin version against 1.3 to identify exposed sites

Monitoring Recommendations

Continuously monitor administrative account activity for privilege misuse against plugin functionality
Alert on database errors and anomalous query volumes from the WordPress application user
Track changes to the plugin directory and integrity of plugin files to detect tampering

How to Mitigate CVE-2025-48161

Immediate Actions Required

Identify all WordPress sites running the YaySMTP plugin and confirm installed version against 1.3
Upgrade YaySMTP to a fixed release once published by YayCommerce
Restrict administrative access using strong authentication and multi-factor authentication on WordPress accounts
Review database audit logs for evidence of injection attempts or unauthorized data access

Patch Information

Review the Patchstack SQL Injection Advisory for vendor-supplied patch status. Apply the updated YaySMTP plugin version when released by YayCommerce through the WordPress plugin repository.

Workarounds

Deactivate and remove the YaySMTP plugin until a patched version is available
Restrict access to the WordPress administrative interface using IP allowlisting at the web server or firewall layer
Enforce least-privilege on the WordPress database user, removing rights such as FILE, CREATE, or DROP where not required
Deploy a WAF with WordPress-specific SQL injection rule sets in blocking mode

bash

# Example: restrict WordPress admin access to trusted IPs in Nginx
location ~ ^/wp-admin/ {
    allow 203.0.113.0/24;
    deny all;
    try_files $uri $uri/ /index.php?$args;
}