CVE-2026-34788: Emlog SQL Injection Vulnerability

CVE-2026-34788 Overview

CVE-2026-34788 is a SQL Injection vulnerability affecting Emlog, an open source website building system. In versions 2.6.2 and prior, the updateTagName() function in include/model/tag_model.php at line 168 directly interpolates user input into SQL query strings without using parameterized queries or proper escaping via $this->db->escape_string(). This improper input sanitization makes the application vulnerable to SQL injection attacks, potentially allowing attackers to read, modify, or delete database contents.

Critical Impact

Authenticated attackers with high privileges can exploit this SQL injection vulnerability to compromise database confidentiality and integrity, potentially extracting sensitive data or modifying database records.

Affected Products

• Emlog versions 2.6.2 and prior

Discovery Timeline

• 2026-04-03 - CVE CVE-2026-34788 published to NVD
• 2026-04-07 - Last updated in NVD database

Technical Details for CVE-2026-34788

Vulnerability Analysis

This SQL injection vulnerability arises from unsafe database query construction in Emlog's tag management functionality. The updateTagName() function located in include/model/tag_model.php at line 168 fails to properly sanitize user-supplied input before incorporating it into SQL queries. Instead of utilizing parameterized queries or the available $this->db->escape_string() method for proper escaping, the function directly concatenates user input into the query string. This classic SQL injection pattern allows attackers to break out of the intended query structure and inject malicious SQL commands.

The vulnerability requires network access and high privileges to exploit, meaning an attacker would need authenticated access to the Emlog administrative interface. Once exploited, the vulnerability can result in high impact to both confidentiality and integrity of the database, though availability is not directly affected.

Root Cause

The root cause is classified as CWE-89 (Improper Neutralization of Special Elements used in an SQL Command). The updateTagName() function uses direct string interpolation to construct SQL queries rather than prepared statements or proper input escaping. This allows specially crafted input containing SQL metacharacters to modify the intended query logic.

Attack Vector

The attack vector is network-based, requiring an authenticated attacker with high privileges to access the vulnerable tag management functionality. The attacker would supply malicious input through the tag name update feature, injecting SQL commands that would be executed against the underlying database. Successful exploitation could enable unauthorized data extraction, modification of database records, or bypass of application-level access controls.

The vulnerability mechanism occurs when user-controlled input is passed to the updateTagName() function and directly embedded into the SQL query without sanitization. An attacker can inject SQL syntax to alter query behavior, such as UNION-based injection to extract data from other tables or boolean-based injection to infer database contents. For detailed technical information, refer to the GitHub Security Advisory.

Detection Methods for CVE-2026-34788

Indicators of Compromise

• Unusual SQL error messages in application logs indicating malformed queries or injection attempts
• Unexpected database queries containing SQL keywords like UNION, SELECT, OR 1=1, or comment sequences (--, /**/)
• Abnormal access patterns to the tag management functionality in Emlog administrative areas
• Database audit logs showing queries accessing tables beyond normal tag operations

Detection Strategies

• Deploy Web Application Firewall (WAF) rules to detect and block common SQL injection patterns in HTTP requests
• Monitor application logs for SQL syntax errors that may indicate injection attempts
• Implement database activity monitoring to detect anomalous query patterns or unauthorized data access
• Use SentinelOne Singularity to detect post-exploitation activities and lateral movement following database compromise

Monitoring Recommendations

• Enable verbose logging for the Emlog application to capture all database queries
• Configure alerts for failed SQL queries and database errors in the tag management module
• Monitor for bulk data extraction attempts that could indicate successful SQL injection exploitation
• Review administrative user activity logs for suspicious tag update operations

How to Mitigate CVE-2026-34788

Immediate Actions Required

• Restrict access to the Emlog administrative interface to trusted IP addresses only
• Implement additional authentication controls for the tag management functionality
• Deploy Web Application Firewall rules to filter SQL injection attempts targeting the vulnerable endpoint
• Consider temporarily disabling the tag renaming feature until a patch is available

Patch Information

At the time of publication, there are no publicly available patches for this vulnerability. Organizations should monitor the GitHub Security Advisory for updates regarding official fixes from the Emlog maintainers.

Workarounds

• Apply input validation at the application or WAF level to reject tag names containing SQL metacharacters
• Implement network-level access controls to limit who can reach the Emlog administrative interface
• Consider manually patching the include/model/tag_model.php file to use $this->db->escape_string() on user input
• Deploy database-level restrictions to limit the privileges of the Emlog database user

Network access restrictions and WAF rules should be configured to protect the vulnerable endpoint. For example, limiting administrative access and filtering malicious input patterns can reduce exposure until an official patch is released. Consult the GitHub Security Advisory for the latest mitigation guidance from the project maintainers.