CVE-2026-9542 Overview
CVE-2026-9542 is a SQL injection vulnerability in CodeAstro Leave Management System version 1.0. The flaw resides in the /admin/add_staff.php script, where the email_id parameter is passed to a backend database query without proper sanitization. An authenticated remote attacker with low privileges can manipulate the parameter to inject arbitrary SQL statements. A public exploit is referenced in third-party vulnerability databases, increasing the likelihood of opportunistic abuse. The weakness is classified under CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component.
Critical Impact
Remote attackers with low-privilege access can inject SQL through the email_id parameter to read, modify, or exfiltrate staff and leave records stored in the application database.
Affected Products
- CodeAstro Leave Management System 1.0
- /admin/add_staff.php administrative endpoint
- Backend MySQL/MariaDB database supporting the application
Discovery Timeline
- 2026-05-26 - CVE-2026-9542 published to NVD
- 2026-05-26 - Last updated in NVD database
Technical Details for CVE-2026-9542
Vulnerability Analysis
The vulnerability exists in the staff creation workflow of CodeAstro Leave Management System 1.0. The /admin/add_staff.php endpoint accepts an email_id value from the request and concatenates it directly into a SQL statement. Because the application does not use parameterized queries or input validation, attacker-controlled characters such as single quotes and SQL keywords reach the database engine unchanged.
Exploitation requires only network access and a low-privileged administrative session. Successful injection allows attackers to read arbitrary tables, alter staff records, or escalate the attack by extracting credential hashes. Public proof-of-concept information is available through the GitHub CVE Issue Report and VulDB Vulnerability #365603.
Root Cause
The root cause is improper neutralization of user-supplied input before inclusion in an SQL query [CWE-74]. The email_id field is treated as trusted text rather than as a bound parameter, allowing query structure modification at runtime.
Attack Vector
The attack vector is remote over the network. An attacker submits a crafted POST request to /admin/add_staff.php with malicious SQL payloads in the email_id parameter. The server returns differential responses or executes injected statements, enabling boolean-based, union-based, or time-based injection techniques.
No verified exploit code is reproduced here. Refer to the VulDB CTI for #365603 entry for technical indicators referenced by the submitter.
Detection Methods for CVE-2026-9542
Indicators of Compromise
- HTTP POST requests to /admin/add_staff.php containing SQL meta-characters such as ', --, UNION, SLEEP(, or INFORMATION_SCHEMA in the email_id field.
- Unexpected database errors logged by the PHP application after staff creation attempts.
- New or modified administrator accounts in the staff table that do not correspond to legitimate provisioning activity.
Detection Strategies
- Inspect web server access logs for requests to /admin/add_staff.php that contain encoded SQL syntax or anomalously long email_id values.
- Deploy a web application firewall (WAF) rule that flags or blocks SQL injection signatures targeting the staff creation endpoint.
- Correlate authentication events for the admin panel with database error spikes to identify probing behavior.
Monitoring Recommendations
- Enable verbose query logging on the backing database and alert on queries originating from the application user that contain UNION SELECT or stacked statements.
- Monitor for outbound data transfers from the application server immediately following admin panel activity.
- Track creation timestamps in the staff and audit tables for entries inserted outside of normal administrative hours.
How to Mitigate CVE-2026-9542
Immediate Actions Required
- Restrict network access to the /admin/ directory using IP allow-listing or VPN-only access until a patched build is deployed.
- Rotate credentials for any administrative accounts that may have been exposed through the application database.
- Review the staff and related tables for unauthorized inserts or modifications since deployment.
Patch Information
No vendor patch has been published in the referenced advisories at the time of NVD publication. Track the CodeAstro Security Insights page and the GitHub CVE Issue Report for fix availability. Until a patch is released, apply compensating controls described below.
Workarounds
- Replace inline SQL concatenation in /admin/add_staff.php with prepared statements using PDO or mysqli parameter binding.
- Apply server-side validation that restricts email_id to RFC 5322 email syntax before any database interaction.
- Deploy a WAF rule that blocks SQL meta-characters in the email_id parameter for the affected endpoint.
# Example ModSecurity rule to block SQLi attempts on the vulnerable parameter
SecRule REQUEST_URI "@streq /admin/add_staff.php" \
"phase:2,chain,deny,status:403,id:1009542,msg:'CVE-2026-9542 SQLi attempt on email_id'"
SecRule ARGS:email_id "@detectSQLi" "t:none,t:urlDecodeUni"
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
