CVE-2026-53690: Redeight CMS SQL Injection Vulnerability

CVE-2026-53690 Overview

CVE-2026-53690 is a critical SQL Injection vulnerability affecting Redeight CMS version 1.0. The flaw resides in the userEmail parameter of the POST /admin/index.php login endpoint. The application concatenates user-supplied input directly into SQL queries without prepared statements or sanitization. Unauthenticated remote attackers can inject arbitrary SQL commands, extract database contents, and bypass authentication controls. The weakness is classified under [CWE-89] Improper Neutralization of Special Elements used in an SQL Command.

Critical Impact

Unauthenticated attackers can extract sensitive database contents and bypass admin authentication by injecting SQL through the login endpoint.

Affected Products

• Redeight CMS version 1.0
• /admin/index.php login endpoint
• Deployments exposing the admin panel to untrusted networks

Discovery Timeline

• 2026-06-30 - CVE CVE-2026-53690 published to NVD
• 2026-06-30 - Last updated in NVD database

Technical Details for CVE-2026-53690

Vulnerability Analysis

The vulnerability exists in the administrative login handler of Redeight CMS 1.0. When a user submits credentials to /admin/index.php, the userEmail POST parameter is interpolated directly into a SQL query used for authentication. Because the query is built through string concatenation rather than parameterized statements, attacker-controlled SQL syntax is treated as part of the query structure.

Exploitation requires no authentication, no user interaction, and only network access to the admin endpoint. Successful injection allows attackers to enumerate schema information, extract user credentials, and manipulate authentication logic to log in as an administrator.

Root Cause

The root cause is missing input validation and the absence of prepared statements in the login query construction. Developer trust in client-supplied userEmail values, combined with direct string interpolation into the SQL statement, permits injection of arbitrary SQL fragments. This aligns with the [CWE-89] classification for SQL injection.

Attack Vector

The attack vector is remote and network-based. An attacker sends a crafted HTTP POST request to /admin/index.php with a malicious userEmail value. Typical payloads use tautology-based conditions or UNION SELECT clauses to bypass authentication or exfiltrate database rows. Time-based and error-based techniques also apply given the direct interpolation.

The vulnerability is described in prose only; no verified proof-of-concept code is published. Refer to the CERT Poland CVE Analysis for additional technical context.

Detection Methods for CVE-2026-53690

Indicators of Compromise

• POST requests to /admin/index.php containing SQL metacharacters such as ', --, /*, UNION, or SELECT in the userEmail field.
• Repeated failed login attempts followed by a successful admin session from the same source IP.
• Unusual database errors surfaced in web server or application logs correlated with admin login traffic.
• Outbound data transfers or large response sizes from the /admin/index.php endpoint.

Detection Strategies

• Deploy web application firewall rules that flag SQL keywords and quote characters submitted to the userEmail parameter.
• Enable database query logging and alert on queries containing concatenated userEmail values with SQL syntax.
• Correlate HTTP access logs with database error logs to identify injection attempts against the admin login endpoint.

Monitoring Recommendations

• Monitor authentication logs for anomalous admin logins that occur without prior valid credential submissions.
• Track HTTP request payload sizes and character distributions targeting /admin/index.php.
• Alert on new administrative accounts, privilege changes, or bulk data reads from CMS database tables.

How to Mitigate CVE-2026-53690

Immediate Actions Required

• Restrict network access to /admin/index.php using IP allowlists, VPN, or reverse proxy authentication until a patch is applied.
• Deploy WAF signatures that block SQL injection patterns targeting the userEmail POST parameter.
• Rotate all administrative credentials and database service account passwords in case prior exploitation occurred.
• Audit the CMS database for unauthorized accounts, modified records, and suspicious query history.

Patch Information

No vendor patch information is currently listed in the NVD entry. Consult the CERT Poland CVE Analysis for vendor coordination status and remediation guidance. Operators should replace concatenated SQL with prepared statements using bound parameters for the userEmail field.

Workarounds

• Place the admin panel behind an authenticated reverse proxy or HTTP basic authentication layer.
• Apply strict server-side input validation that rejects any userEmail value containing SQL metacharacters.
• Implement a WAF rule set such as OWASP CRS with SQL injection protections enabled in blocking mode.
• Disable or remove the vulnerable Redeight CMS 1.0 instance from public-facing infrastructure until remediation is available.

# Example ModSecurity rule to block SQLi in userEmail parameter
SecRule ARGS:userEmail "@detectSQLi" \
  "id:1005390,\
   phase:2,\
   deny,\
   status:403,\
   msg:'Potential SQL Injection in userEmail (CVE-2026-53690)',\
   tag:'CWE-89'"