CVE-2026-78171: Sales and Inventory System SQLi Vulnerability

CVE-2026-78171 Overview

CVE-2026-78171 is a SQL injection vulnerability in itsourcecode Sales and Inventory System 1.0. The flaw resides in the /pages/processlogin.php file, where the User parameter is passed to a database query without proper sanitization. Remote attackers can manipulate the parameter to inject arbitrary SQL statements against the backend database. The exploit has been publicly disclosed, increasing the likelihood of opportunistic exploitation against exposed instances. The weakness is classified under [CWE-74] (Improper Neutralization of Special Elements in Output Used by a Downstream Component).

Critical Impact
Unauthenticated remote attackers can inject SQL through the login form, potentially exposing credentials, bypassing authentication, and reading or modifying data in the sales and inventory database.

Affected Products

itsourcecode Sales and Inventory System 1.0
Vulnerable component: /pages/processlogin.php
Vulnerable parameter: User

Discovery Timeline

2026-08-24 - CVE-2026-78171 published to NVD
2026-08-26 - Last updated in NVD database

Technical Details for CVE-2026-78171

Vulnerability Analysis

The vulnerability is a classic SQL injection in the login processing script of the Sales and Inventory System. The processlogin.php handler accepts the User argument submitted through the login workflow and concatenates it directly into a SQL query. Because the input is neither parameterized nor escaped, attackers can terminate the intended query and append arbitrary SQL clauses. Successful exploitation impacts confidentiality, integrity, and availability of the underlying database. The attack requires no authentication and no user interaction, and it can be delivered over the network.

Root Cause

The root cause is improper neutralization of special characters in a database query [CWE-74]. The User parameter received from the login form is trusted as-is and interpolated into the SQL statement executed by the PHP backend. The application does not use prepared statements, parameter binding, or input validation to prevent SQL metacharacters such as single quotes, comments, or boolean operators from altering query structure.

Attack Vector

An attacker sends a crafted HTTP POST request to /pages/processlogin.php with a malicious value in the User field. Payloads that terminate the string context and append boolean or UNION-based clauses can bypass authentication or exfiltrate data through in-band or blind techniques. Because the endpoint is exposed pre-authentication, exploitation requires only reachability to the web application over the network.

No verified proof-of-concept code is included here. Technical detail is referenced in the VulDB CVE-2026-78171 entry and the GitHub issue tracker.

Detection Methods for CVE-2026-78171

Indicators of Compromise

HTTP POST requests to /pages/processlogin.php containing SQL metacharacters in the User parameter, such as single quotes, --, #, OR 1=1, or UNION SELECT.
Web server or application logs showing authentication attempts with unusually long or encoded User values.
Database error messages returned to clients referencing SQL syntax or column mismatches originating from the login endpoint.

Detection Strategies

Deploy web application firewall (WAF) signatures that inspect POST bodies to processlogin.php for SQL injection patterns.
Enable verbose access logging on the web server and alert on repeated failed logins from a single source targeting the User parameter.
Correlate web request logs with database query logs to identify anomalous query structures originating from the login handler.

Monitoring Recommendations

Monitor the login endpoint for spikes in request volume, non-browser user agents, and automated scanning tools such as sqlmap.
Alert on database sessions from the web application account executing INFORMATION_SCHEMA queries or UNION-based statements outside of expected application logic.

How to Mitigate CVE-2026-78171

Immediate Actions Required

Restrict network exposure of the Sales and Inventory System by placing it behind a VPN or IP allow-list until a fix is applied.
Deploy WAF rules blocking SQL injection payloads targeting /pages/processlogin.php and the User parameter specifically.
Rotate database and application credentials if logs indicate the endpoint may already have been probed.

Patch Information

No vendor patch is referenced in the CVE data at the time of publication. Consult the IT Source Code project page and the GitHub issue tracker for updates from the maintainer. Until an official fix is released, apply the workarounds below.

Workarounds

Rewrite the processlogin.php query logic to use parameterized statements with PDO or MySQLi prepared statements instead of string concatenation.
Apply strict server-side input validation on the User field, rejecting characters outside an expected alphanumeric character set.
Enforce least-privilege permissions on the database account used by the web application so that a successful injection cannot alter schema or read unrelated tables.
Enable database query logging and review for anomalous statements originating from the application service account.

bash

# Example hardening: constrain the DB account used by the app
REVOKE ALL PRIVILEGES ON *.* FROM 'sales_app'@'localhost';
GRANT SELECT, INSERT, UPDATE ON sales_inventory.* TO 'sales_app'@'localhost';
FLUSH PRIVILEGES;