CVE-2026-111853 in 3 Series MDO
Summary
by MITRE • 10/17/2026
An issue was discovered on Tektronix 3 Series MDO devices before 1.21.1. An OS command injection vulnerability exists in the FILESystem:MOUNT:DRIve SCPI command handler. Insufficient neutralization of user-supplied input allows remote attackers to execute arbitrary operating system commands with elevated privileges.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 10/17/2026
The Tektronix 3 Series Mixed Domain Oscilloscopes (MDO) represent a class of sophisticated test and measurement instruments widely deployed in engineering, research, and industrial environments for signal analysis and debugging. These devices are increasingly connected to laboratory networks to facilitate automated testing workflows, data logging, and remote control via Standard Commands for Programmable Instruments SCPI protocol. The discovery of an operating system command injection vulnerability within the FILESystem:MOUNT:DRIve SCSCMD handler in firmware versions prior to 1.21.1 exposes a critical security flaw that undermines the integrity and confidentiality of these instruments. This specific component is responsible for managing storage media, such as USB drives or internal memory partitions, allowing users to mount different drive directories on the device. The vulnerability arises from insufficient input validation within this command handler, which fails to adequately sanitize user-supplied data before passing it to underlying operating system shell commands.
From a technical perspective, the flaw constitutes an OS Command Injection, categorized under CWE-78 in the Common Weakness Enumeration taxonomy. This type of vulnerability occurs when software constructs system-level commands using unsanitized input from users or external sources. In this specific instance, the SCPI command parser accepts parameters intended to specify drive paths but does not properly escape special characters that have meaning to the shell interpreter, such as semicolons, ampersands, or pipe symbols. Consequently, a remote attacker who can communicate with the oscilloscope over its network interface can craft maliciously formatted commands. By injecting additional command sequences into the mount request payload, the attacker tricks the device's operating system into executing arbitrary code alongside the intended file mounting operation. This exploitation path is particularly dangerous because it does not require physical access to the device or prior authentication in many default configurations, allowing for unauthenticated remote exploitation over TCP/IP connections that are standard in modern laboratory setups.
The operational impact of this vulnerability is severe due to the privilege level at which the injected commands execute. The SCPI command handler typically runs with elevated privileges, often root-level access on embedded Linux systems commonly used in such hardware. Successful exploitation allows an attacker to gain full control over the operating system running on the oscilloscope. This capability enables a range of malicious activities including data exfiltration where sensitive measurement data or proprietary test results are stolen, persistence mechanisms that allow long-term unauthorized access even after reboots, and lateral movement within the laboratory network if the device is used as a pivot point to attack other connected systems such as design automation servers or configuration management databases. Furthermore, attackers could modify firmware updates or tamper with calibration data, leading to inaccurate measurements that compromise engineering decisions and product quality in manufacturing environments.
This vulnerability aligns with MITRE ATT&CK techniques related to Command and Scripting Interpreter abuse, specifically T1059 which covers execution of commands via system shells. The attack vector is classified as Remote Code Execution through a network service, falling under the Initial Access or Persistence tactics depending on how the compromised device is utilized post-exploitation. Given that test equipment often contains valuable intellectual property and connects to critical infrastructure control systems in industrial settings, the risk extends beyond simple data loss to potential operational disruption. The lack of input sanitization highlights a gap in secure coding practices during the development of embedded SCPI handlers, where developers may prioritize functional correctness over security hardening assumptions about network trust boundaries.
Mitigation strategies must focus on immediate patching and defensive configuration changes until updates are applied. Tektronix has addressed this issue by releasing firmware version 1.21.1 which implements proper input validation and sanitization routines within the FILESystem:MOUNT:DRIve command handler to prevent shell metacharacter injection. Organizations should prioritize updating all affected devices in their inventory immediately upon availability of the patched firmware. In environments where immediate patching is not feasible due to operational constraints, network segmentation strategies should be employed to restrict access to these instruments from untrusted networks or general-purpose workstations. Access control lists on firewalls and switches can limit SCPI port connectivity to only authorized automation servers that require such interaction. Additionally enabling strict logging of all SCPI commands allows for the detection of anomalous command patterns indicative of injection attempts, providing a layer of monitoring defense while technical remediation is pending.