CVE-2026-18896: Student Registration System SQLi Flaw

CVE-2026-18896 Overview

CVE-2026-18896 is a SQL injection vulnerability in lavkush-maurya Student-Registration-System version 1.0. The flaw resides in the /student/changepass.php script, where the oldpass request parameter is passed to a database query without proper sanitization. Attackers can manipulate this parameter to inject arbitrary SQL statements against the backend database. The vulnerability is exploitable remotely and requires only low-level authenticated access to the application. Public exploitation details have been disclosed, and the vendor did not respond to disclosure attempts. The weakness is classified under CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component.

Critical Impact
Authenticated attackers can inject SQL through the oldpass parameter of /student/changepass.php, enabling data extraction, credential compromise, and potential integrity impact on the student database.

Affected Products

lavkush-maurya Student-Registration-System 1.0
/student/changepass.php password-change endpoint
Backend MySQL/MariaDB database instances used by the application

Discovery Timeline

2026-08-05 - CVE-2026-18896 published to NVD
2026-08-05 - Last updated in NVD database

Technical Details for CVE-2026-18896

Vulnerability Analysis

The vulnerability affects the password-change workflow of the Student-Registration-System web application. When a user submits the change-password form, the changepass.php script receives the oldpass parameter and concatenates it directly into a SQL query used to verify the current password. Because the parameter is not sanitized, escaped, or bound as a prepared-statement placeholder, an attacker can break out of the string context and append additional SQL clauses.

A successful attacker can read arbitrary rows from application tables, including credential material for other students or administrators. Depending on database privileges, the same primitive supports data modification and potential lateral movement inside the database engine. Exploitation requires an authenticated low-privilege session, and no user interaction is needed beyond submitting a crafted HTTP request. The disclosure notes public availability of the exploit technique via the referenced GitHub SQL Injection Documentation.

Root Cause

The root cause is direct interpolation of untrusted request data into a SQL statement without parameterization. The oldpass value flows from the HTTP request into a query string used by changepass.php, violating [CWE-74] injection-safe output guidance. The developer did not adopt prepared statements or a database abstraction layer, so any special characters in the input are treated as SQL syntax.

Attack Vector

An authenticated attacker sends a crafted POST request to /student/changepass.php, supplying a malicious payload in the oldpass field. Time-based, boolean-based, and UNION-based techniques are all applicable, as documented in the public write-up. The attack traverses the network and does not require local access to the host running the application.

No verified exploit code is reproduced here. Refer to the VulDB CVE-2026-18896 entry and the public GitHub write-up for technical details.

Detection Methods for CVE-2026-18896

Indicators of Compromise

HTTP POST requests to /student/changepass.php containing SQL metacharacters such as ', --, UNION, SLEEP(, or BENCHMARK( in the oldpass parameter.
Anomalous response latency on the change-password endpoint, indicating time-based SQL injection probing.
Web server or PHP error logs referencing SQL syntax errors originating from changepass.php.
Database audit entries showing queries against user or credential tables initiated by the web application user during a password-change flow.

Detection Strategies

Deploy a web application firewall rule that flags SQL injection patterns targeting the oldpass POST parameter on /student/changepass.php.
Enable database query logging and alert on queries that reference multiple tables when originating from changepass.php.
Correlate authentication events with subsequent SQL error responses to identify authenticated abuse.

Monitoring Recommendations

Monitor HTTP 500 and unusual 200 responses from the change-password endpoint for volumetric spikes.
Track response-time distributions for /student/changepass.php to surface time-based injection attempts.
Forward web server access logs and database audit logs to a centralized analytics platform for retrospective hunting.

How to Mitigate CVE-2026-18896

Immediate Actions Required

Restrict access to the Student-Registration-System deployment to trusted networks until a patched build is available.
Rotate credentials for all application users and any database accounts referenced by the application.
Review web and database logs for signs of prior exploitation targeting /student/changepass.php.
Disable the change-password endpoint or place it behind additional authentication if operationally feasible.

Patch Information

The vendor did not respond to disclosure outreach, and no official patch has been published for lavkush-maurya Student-Registration-System 1.0 at the time of NVD publication on 2026-08-05. Operators should apply source-level fixes by replacing string concatenation in changepass.php with parameterized queries using PDO or mysqli prepared statements, and validate the oldpass input against an allowed character set. Consult the VulDB entry for ongoing status updates.

Workarounds

Modify changepass.php in-place to use prepared statements with bound parameters for the oldpass field.
Deploy a WAF signature that blocks SQL metacharacters in the oldpass POST parameter.
Enforce least-privilege database credentials so the application account cannot read or modify unrelated tables.
Remove the application from internet exposure and restrict it to VPN or internal network access.

bash

# Example ModSecurity rule to block SQLi patterns in the oldpass parameter
SecRule ARGS:oldpass "@rx (?i)(union(\s|/\*.*\*/)+select|sleep\s*\(|benchmark\s*\(|--|;|')" \
    "id:1026188960,phase:2,deny,status:403,log,\
    msg:'CVE-2026-18896 SQLi attempt on changepass.php oldpass parameter'"