CVE-2026-71231 in IOTSmartHome
Summary
by MITRE • 08/05/2026
IOTSmartHome's gui/login.php checkCookie() function builds an authentication query as SELECT * FROM users WHERE ID='<decoded lastLogin cookie>' after base64-decoding the client-supplied lastLogin cookie via safe_decode(), which performs URL-safe base64 decoding with no sanitization of the decoded value before it is concatenated into the SQL string. An unauthenticated attacker can set a lastLogin cookie containing a base64-encoded SQL injection payload (e.g. base64("' OR '1'='1")) to bypass authentication and, via UNION-based injection, extract arbitrary data including user credentials.
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Analysis
by VulDB Data Team • 08/05/2026
The vulnerability identified in IOTSmartHome's gui/login.php file represents a critical sql injection flaw that directly undermines the application's authentication mechanism. The checkCookie() function processes client-supplied cookies without proper input validation or sanitization, creating an avenue for malicious actors to manipulate the authentication flow. This weakness stems from the application's reliance on base64-encoded cookie values while failing to implement adequate security measures during the decoding and query construction phases.
The technical implementation flaw occurs when the safe_decode() function performs url-safe base64 decoding of the lastLogin cookie value without any subsequent sanitization or parameterization of the decoded content. The decoded value is then directly concatenated into a sql select statement, creating an environment where malicious input can alter the intended query structure. This pattern aligns with common sql injection vulnerabilities classified under cwe-89 and specifically demonstrates improper neutralization of special elements used in sql commands. The vulnerability operates at the application layer where user-controllable data flows directly into database queries without proper sanitization.
The operational impact of this vulnerability extends beyond simple authentication bypass, as it provides attackers with the capability to extract arbitrary data from the underlying database system. An unauthenticated attacker can craft a malicious lastLogin cookie containing sql injection payloads that, when base64-encoded and submitted to the application, will execute unintended sql commands. Through union-based sql injection techniques, the attacker can retrieve sensitive information including user credentials, personal data, and potentially system configuration details. This vulnerability directly maps to attack techniques documented in the attack pattern taxonomy under t1213 database credential access and t1203 sql injection.
Mitigation strategies must address both immediate remediation and architectural improvements to prevent similar vulnerabilities from occurring. The most critical fix involves implementing proper sql parameterization or prepared statements that separate sql command structure from data values, effectively neutralizing the injection vector. Input validation and sanitization should be implemented at the point of cookie decoding to ensure no malicious content can influence query construction. Additionally, the application should implement proper authentication logging and monitoring to detect anomalous cookie patterns that may indicate attempted exploitation. Security best practices recommend applying the principle of least privilege for database connections and implementing web application firewalls to filter suspicious sql injection attempts. The vulnerability demonstrates the importance of following secure coding guidelines such as those specified in owasp top ten and iso/iec 27001 security controls for protecting against sql injection attacks.