CVE-2026-103946 in Nessus
Summary
by MITRE • 10/15/2026
An SQL injection vulnerability could allow an authenticated user to read or modify data stored by Nessus.
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Analysis
by VulDB Data Team • 10/15/2026
The identified security flaw represents a critical failure in input validation and query construction within the Nessus application, specifically affecting components accessible only after successful authentication. This classification as an SQL injection vulnerability indicates that the software fails to properly sanitize user-supplied data before incorporating it into dynamic database queries. While many modern frameworks employ parameterized queries or prepared statements to inherently mitigate such risks, this specific implementation appears to rely on string concatenation or insufficient escaping mechanisms for certain input fields. The requirement for authentication suggests that while the attack surface is restricted compared to unauthenticated remote code execution vectors, the potential impact remains severe due to the privileged context in which the malicious SQL commands are executed.
From a technical perspective, this vulnerability allows an authenticated attacker to manipulate the structure of backend database queries. By injecting carefully crafted SQL syntax into input parameters, such as search fields, filter options, or API payloads, the attacker can alter the intended logic of the query. This capability enables several distinct attack vectors including blind boolean-based injection, time-based inference, and direct data extraction via union-based techniques. The core technical flaw lies in the lack of strict type checking and context-aware encoding of user inputs before they are processed by the database engine. Consequently, the application treats malicious input as executable code rather than passive data, leading to unauthorized interactions with the underlying relational database management system.
The operational impact of this vulnerability is substantial, primarily centering on the compromise of confidentiality and integrity for sensitive organizational data stored within Nessus. Attackers can exploit this flaw to exfiltrate critical information such as scan results, credential hashes, plugin configurations, and user account details. Beyond passive reading, the ability to modify data introduces significant risks to system integrity. An attacker could alter vulnerability scores, suppress specific findings to hide security gaps from administrators, or even inject malicious payloads into stored records that may be processed by other systems integrated with Nessus. In environments where Nessus serves as a central hub for compliance reporting and risk assessment, such tampering can lead to false negatives in security postures and potentially facilitate further lateral movement within the network if sensitive credentials are harvested from the database.
This vulnerability aligns closely with Common Weakness Enumeration identifier CWE-89, which describes Improper Neutralization of Special Elements used in an SQL Command. The exploitation technique typically falls under MITRE ATT&CK tactic T1059, specifically sub-technique T1059.004 for Command and Scripting Interpreter interactions via database commands, or more broadly within the Data Exfiltration techniques found in TA0010 if data is stolen, or Impact tactics like TA0040 if integrity is compromised through modification of stored records. The presence of this flaw underscores a gap in secure coding practices regarding input validation for authenticated endpoints, highlighting that authentication alone does not guarantee protection against injection attacks when backend query construction is flawed.
To mitigate the immediate risk and prevent future occurrences, developers must implement strict parameterized queries or prepared statements for all database interactions involving user-supplied data. This approach ensures that inputs are treated strictly as data parameters rather than executable code fragments. Additionally, implementing robust input validation using allow-listing strategies can restrict acceptable characters to a predefined set of safe values based on the expected data type and format. Deploying Web Application Firewalls with specific rulesets for SQL injection patterns may provide an additional layer of defense in depth, though it should not replace secure coding practices. Regular security code reviews focusing on database interaction layers and automated static application security testing tools configured to detect dynamic query construction are essential steps toward hardening the application against such vulnerabilities.