CVE-2026-18667 in Sensor Proxy
Summary
by MITRE • 08/04/2026
A vulnerability in Tenable Sensor Proxy allows a remote attacker to execute code with elevated privileges by inducing an operator to connect the sensor to an attacker-controlled host.
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Analysis
by VulDB Data Team • 08/04/2026
This vulnerability represents a critical security flaw in Tenable's sensor proxy component that enables remote code execution with elevated privileges through a sophisticated social engineering attack vector. The vulnerability stems from insufficient validation of connection endpoints during the sensor provisioning process, where an attacker can manipulate the sensor to establish communication with a malicious host rather than the legitimate management server. This misconfiguration allows the attacker to inject malicious payloads that execute with the privileges of the sensor proxy service, typically running with system-level access.
The technical implementation of this vulnerability involves a man-in-the-middle attack pattern where the sensor proxy fails to properly authenticate or validate the identity of remote hosts during connection establishment. When an operator connects the sensor to an attacker-controlled host, the proxy accepts the connection without sufficient cryptographic verification or endpoint authentication mechanisms. This flaw aligns with CWE-295 which addresses improper certificate validation and CWE-310 which covers cryptographic issues in authentication protocols. The vulnerability exploits the trust relationship between sensor and management components, allowing attackers to leverage the sensor's elevated privileges for further compromise of the network infrastructure.
The operational impact of this vulnerability extends beyond immediate code execution capabilities to encompass complete network infiltration and persistent access. Once executed, the attacker gains access to the sensor proxy's full operational capabilities including network scanning permissions, credential harvesting, and potential lateral movement within the compromised environment. The sensor proxy typically operates with elevated privileges due to its role in network monitoring and security scanning functions, making it an attractive target for attackers seeking privileged access. This vulnerability directly maps to attack techniques in the MITRE ATT&CK framework under T1059 for command and scripting interpreter and T1566 for credential harvesting through social engineering approaches.
Organizations should implement immediate mitigations including network segmentation of sensor proxy components, mandatory certificate validation enforcement, and operator training on connection verification procedures. The recommended approach involves deploying strict connection policies that require explicit certificate validation before establishing communication with any remote host. Additionally, organizations should consider implementing automated monitoring for unauthorized sensor connections and establish secure provisioning processes that prevent operators from inadvertently connecting sensors to untrusted hosts. Regular security audits of sensor proxy configurations and network access controls are essential to maintain defense in depth against this class of vulnerability.