CVE-2026-81203: Simple Online Food Ordering System SQLi

CVE-2026-81203 Overview

CVE-2026-81203 is a SQL injection vulnerability in SourceCodester Simple Online Food Ordering System 1.0. The flaw affects the /admin/ajax.php?action=login2 endpoint, where the email parameter is passed unsanitized into a database query. Remote attackers can exploit the issue without authentication to manipulate SQL statements executed by the application backend. The exploit details have been publicly disclosed, increasing the likelihood of opportunistic scanning against exposed installations. The weakness is tracked under CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component).

Critical Impact
Unauthenticated remote attackers can inject SQL statements through the administrative login endpoint, potentially exposing credentials and administrative data stored in the application database.

Affected Products

SourceCodester Simple Online Food Ordering System 1.0
The vulnerable file is /admin/ajax.php when invoked with action=login2
The vulnerable parameter is email

Discovery Timeline

2026-08-26 - CVE-2026-81203 published to NVD
2026-08-26 - Last updated in NVD database

Technical Details for CVE-2026-81203

Vulnerability Analysis

The vulnerability resides in the administrative authentication handler at /admin/ajax.php?action=login2. The email request parameter is concatenated into a SQL query without parameterization or input validation. An attacker submitting a crafted email value can break out of the intended string context and append arbitrary SQL clauses.

Because the endpoint is reachable before authentication, exploitation requires no valid credentials. The attack is executed remotely over the network with low complexity. Successful injection can extract administrator credentials, bypass login checks, or enumerate other tables in the food ordering database.

Root Cause

The root cause is improper neutralization of user-supplied input in a SQL query, classified under CWE-74. The login2 action in ajax.php builds a query string by directly embedding the email POST parameter. Prepared statements or parameterized queries are not used, and no server-side sanitization is applied.

Attack Vector

An unauthenticated attacker sends an HTTP POST request to /admin/ajax.php?action=login2 with a malicious email value. The payload alters the query logic and forces the backend to return data controlled by the attacker or authenticate the session under false conditions. See the GitHub issue tracker and VulDB vulnerability details for reproduction context.

The vulnerability manifests during query construction in the login2 handler. No verified proof-of-concept code has been published in a form suitable for inclusion; refer to the VulDB CVE listing for additional technical context.

Detection Methods for CVE-2026-81203

Indicators of Compromise

HTTP POST requests to /admin/ajax.php?action=login2 containing SQL metacharacters such as single quotes, UNION, SELECT, --, or /* in the email parameter
Web server or application logs showing repeated authentication requests with unusually long or malformed email values
Database error messages referencing syntax errors originating from the login2 handler

Detection Strategies

Deploy web application firewall (WAF) rules that inspect the email parameter on the /admin/ajax.php path for SQL injection signatures
Enable database query logging and alert on unexpected UNION, INFORMATION_SCHEMA, or authentication-bypass patterns tied to the ordering application user
Correlate failed login bursts on the admin panel with anomalous response sizes, which often signal successful data exfiltration through injection

Monitoring Recommendations

Baseline normal request patterns to /admin/ajax.php and alert on deviations in payload length, character distribution, or source IP diversity
Forward web and database logs to a centralized platform for retention and cross-source correlation
Track outbound connections from the application host that follow suspicious admin requests, which may indicate post-exploitation activity

How to Mitigate CVE-2026-81203

Immediate Actions Required

Restrict network access to the /admin/ directory using IP allowlists, VPN gating, or authentication at the reverse proxy layer
Deploy WAF signatures that block SQL injection payloads targeting the email parameter on the login2 action
Audit the application database for unauthorized administrator accounts, modified records, or exfiltration indicators

Patch Information

At the time of publication, no official vendor patch has been referenced in the advisory. Monitor the SourceCodester resource hub and the VulDB CVE listing for remediation updates. Organizations operating the affected version should evaluate replacing the login handler with parameterized queries or migrating away from the vulnerable release.

Workarounds

Rewrite the login2 handler in /admin/ajax.php to use prepared statements with bound parameters for the email and password fields
Apply server-side input validation that rejects non-email characters before the value reaches any SQL context
Place the admin interface behind an authenticated reverse proxy so unauthenticated requests never reach the vulnerable endpoint
Rotate all administrator credentials and database secrets after confirming the application is no longer exposed

bash

# Example nginx configuration to restrict /admin/ to a trusted network
location /admin/ {
    allow 10.0.0.0/24;
    deny all;
    proxy_pass http://app_backend;
}