CVE-2025-12252: Carmelo Event Judging System SQLi Flaw

CVE-2025-12252 is an SQL injection vulnerability in Carmelo Online Event Judging System 1.0 affecting the /ajax/action.php file. Attackers can exploit this remotely to compromise databases. This article covers the vulnerability's technical details, affected versions, impact, and mitigation strategies.

CVE-2025-12252 Overview

CVE-2025-12252 is a SQL injection vulnerability in code-projects Online Event Judging System 1.0. The flaw resides in an unspecified function within the /ajax/action.php endpoint. Attackers can manipulate the content parameter to inject arbitrary SQL statements into backend database queries. The vulnerability is exploitable remotely and requires low-privilege authentication. Public exploit details have been disclosed, increasing the likelihood of opportunistic attacks against exposed installations. The issue is tracked under CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component.

Critical Impact
Authenticated remote attackers can inject SQL through the content parameter of /ajax/action.php, potentially exposing or altering judging data stored in the application database.

Affected Products

Carmelo Online Event Judging System 1.0
Component: /ajax/action.php
CPE: cpe:2.3:a:carmelo:online_event_judging_system:1.0

Discovery Timeline

2025-10-27 - CVE-2025-12252 published to the National Vulnerability Database
2026-04-29 - Last updated in NVD database

Technical Details for CVE-2025-12252

Vulnerability Analysis

The vulnerability stems from unsanitized user input passed to a SQL query in /ajax/action.php. The content argument is concatenated directly into a database statement without parameterization or escaping. An attacker submitting crafted payloads alters the structure of the executed SQL, enabling unauthorized data retrieval and modification.

Because the application accepts requests over the network and requires only low-privilege authentication, exploitation can be automated using standard tooling. The disclosure of exploit details in public trackers such as VulDB #329923 and the GitHub CVE Issue Tracker lowers the bar for attackers seeking to weaponize the flaw.

Root Cause

The root cause is improper neutralization of special elements in the content request parameter. The /ajax/action.php handler builds dynamic SQL using string concatenation instead of prepared statements with bound parameters. This permits an attacker to inject SQL meta-characters such as single quotes, semicolons, and comment sequences to break out of the intended query context.

Attack Vector

An authenticated user sends a crafted HTTP request to /ajax/action.php with a malicious value in the content field. The payload terminates the original SQL statement and appends attacker-controlled clauses such as UNION SELECT queries or boolean conditions. Successful exploitation yields read or write access to records managed by the judging system, including judge accounts, event entries, and scoring data.

No authenticated exploit code has been validated by the vendor, but public references confirm reproducibility against version 1.0. See the VulDB CTI #329923 entry for additional context.

Detection Methods for CVE-2025-12252

Indicators of Compromise

HTTP POST or GET requests to /ajax/action.php containing SQL meta-characters such as ', --, ;, UNION, SELECT, or SLEEP( in the content parameter.
Web server access logs showing repeated requests to /ajax/action.php from a single source within a short interval.
Database error messages or stack traces returned to clients after requests to the affected endpoint.

Detection Strategies

Inspect web server and application logs for anomalous content parameter values targeting /ajax/action.php.
Deploy a web application firewall (WAF) rule set that flags common SQL injection patterns directed at the affected endpoint.
Correlate authentication events with subsequent injection attempts to identify compromised low-privilege accounts.

Monitoring Recommendations

Enable verbose query logging on the backing MySQL or MariaDB server to capture queries originating from the application user.
Alert on unexpected UNION or INFORMATION_SCHEMA references in executed SQL statements.
Monitor outbound network traffic from the application host for unusual data egress that may indicate exfiltration of database contents.

How to Mitigate CVE-2025-12252

Immediate Actions Required

Restrict network access to the Online Event Judging System to trusted users and internal networks until a vendor fix is available.
Disable or remove the affected /ajax/action.php endpoint if it is not required for production operations.
Audit existing judge and administrator accounts for unauthorized changes to event records or scoring data.

Patch Information

No official vendor patch is listed for CVE-2025-12252 at the time of publication. Administrators should monitor the code-projects website and the GitHub CVE Issue Tracker for updates. In the absence of a vendor release, source-level remediation requires replacing string-concatenated SQL in /ajax/action.php with parameterized queries using PDO or mysqli prepared statements.

Workarounds

Place the application behind a WAF configured to block SQL injection signatures targeting the content parameter.
Apply database-level least-privilege controls so the application database user cannot read sensitive schemas or execute administrative statements.
Implement server-side input validation that rejects requests containing SQL meta-characters in the content field.

bash

# Example ModSecurity rule to block SQLi attempts against the vulnerable endpoint
SecRule REQUEST_URI "@streq /ajax/action.php" \
  "id:1012252,phase:2,deny,status:403,log,\
   msg:'CVE-2025-12252 SQLi attempt on content parameter',\
   chain"
  SecRule ARGS:content "@rx (?i)(union(\s)+select|--|;|sleep\(|information_schema)" \
    "t:none,t:urlDecode"