CVE-2026-12775: SQL Injection in Montodel House-Rental-Management /login.php

Technical summary

The vulnerability resides in the /login.php file where the Username input parameter is processed without proper sanitization or parameterized queries. By injecting SQL metacharacters (such as single quotes and logical operators), an unauthenticated attacker can break out of the intended SQL query context and execute arbitrary SQL commands. The issue is classified under CWE-74 (Improper Neutralization of Special Elements) and CWE-89 (SQL Injection), reflecting insufficient input validation and reliance on string concatenation for query construction. The CVSS v3.1 score of 7.3 (HIGH) reflects the network-accessible attack vector, low attack complexity, and confidentiality/integrity/availability impact across a single security context.

Business impact

Successful exploitation could grant unauthorized access to rental management data, including tenant information, payment records, and lease details. An attacker could exfiltrate sensitive personal information, modify booking records to create fraudulent transactions, delete audit trails, or even escalate privileges within the application. For property management operators, this represents exposure of customer data (triggering privacy breach notifications), financial loss through unauthorized transactions, and reputational damage. The public availability of exploit code elevates the likelihood of opportunistic attacks against deployed instances.

Affected systems

Montodel House-Rental-Management is affected up to commit 90010017b81265eb1ef3810268909f7719a33863. The product uses a rolling release model without discrete version numbering, making it difficult to identify which deployed instances are vulnerable. Any installation using a commit at or before the noted hash is at risk. Organizations should verify their current deployment hash against the vendor's repository.

Exploitability

The vulnerability is highly exploitable: it requires no authentication, no special configuration, and no user interaction. The attack surface is the public-facing login endpoint (/login.php), which is trivial to discover and probe. The simplicity of SQL injection payloads—combined with publicly disclosed exploit code—means that even moderately skilled attackers can weaponize this flaw. The lack of apparent rate limiting or intrusion detection suggests that reconnaissance and exploitation attempts may go undetected.

Remediation

The Montodel team has not responded to early vendor disclosure and has not released a public patch. Organizations must take immediate remedial action: upgrade to the latest commit in the vendor's repository (verify that the commit hash is newer than 90010017b81265eb1ef3810268909f7719a33863), implement parameterized queries (prepared statements) in the authentication logic, and apply input validation on all user-supplied data. As a temporary measure, deploy a Web Application Firewall (WAF) rule to detect and block SQL injection patterns in the Username parameter.

Patch guidance

Monitor the Montodel House-Rental-Management repository (verify the project URL with your vendor contact) for updates beyond commit 90010017b81265eb1ef3810268909f7719a33863. Given the rolling release model, patches will likely be distributed as new commits; review commit messages and changelogs for SQL injection remediation. Before applying any update, test in a non-production environment to ensure compatibility. If no patch is forthcoming within 30 days, consider switching to an actively maintained alternative or isolating the vulnerable application behind a restrictive WAF ruleset.

Detection guidance

Monitor application logs for unusual SQL syntax in login requests (look for single quotes, SQL keywords like UNION, SELECT, OR in the Username field). Implement database query logging to identify anomalous SQL statements being executed. Deploy a WAF with out-of-the-box SQL injection signatures to block payloads before they reach the application. Set up alerts on failed login attempts with special characters or unusually long payloads. Check database access logs for connections from the web application user account performing unexpected queries or accessing tables outside the normal schema.

Why prioritize this

This vulnerability merits immediate patching because (1) it is network-accessible with no authentication barrier, (2) the attack complexity is low, (3) exploit code is public, and (4) it directly compromises confidentiality, integrity, and availability of the database. The lack of vendor responsiveness and the rolling-release model create uncertainty about remediation timelines, necessitating urgent internal mitigation. Organizations running Montodel House-Rental-Management should treat this as a critical priority.

Risk score, explained

The CVSS 3.1 score of 7.3 (HIGH) reflects: Attack Vector = Network (AV:N) — exploitable remotely; Attack Complexity = Low (AC:L) — no special conditions needed; Privileges Required = None (PR:N) — unauthenticated access; User Interaction = None (UI:N) — no user click or social engineering; Scope = Unchanged (S:U) — impacts only the vulnerable component; and Confidentiality/Integrity/Availability = Low (C:L/I:L/A:L) — partial impact across all three pillars. The score would be higher (9.0–9.9 CRITICAL) if the impact ratings were HIGH, but LOW ratings reflect that while damage is possible, the scope is constrained to database queries rather than system-wide compromise.

Frequently asked questions