CVE-2026-82762 in FX3000 Series
Summary
by MITRE • 09/14/2026
Improper neutralization of special elements used in an OS command ('OS Command Injection') issue exists in Contec FX5000 series, FX4000 series, and FX3000 series. If this vulnerability is exploited, an arbitrary OS command may be executed by an attacker who can log in to the product.
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Analysis
by VulDB Data Team • 09/14/2026
The identified vulnerability represents a classic instance of Operating System Command Injection within Contec’s FX5000, FX4000, and FX3000 series industrial devices. This flaw stems from improper neutralization of special elements used in OS commands, which corresponds directly to CWE-78 in the Common Weakness Enumeration taxonomy. The core technical issue lies in the application's failure to adequately sanitize or validate user-supplied input before it is passed as part of a system-level command execution string. When an attacker provides maliciously crafted data containing shell metacharacters such as semicolons, pipes, ampersands, or backticks, the underlying operating system interprets these characters not as literal text but as instructions to execute additional commands. This breaks the intended isolation between user input and system operations, allowing for arbitrary command execution with the privileges of the vulnerable application process.
The operational impact of this vulnerability is severe due to its potential for complete device compromise. An attacker who successfully authenticates to one of these industrial control systems can leverage this flaw to execute commands at the operating system level. This capability effectively grants the adversary full administrative access, enabling them to modify configurations, install persistent backdoors, exfiltrate sensitive operational data, or disrupt critical processes. In an industrial context, such as manufacturing or infrastructure management, this could lead to physical disruptions, safety hazards, or significant financial losses depending on the specific role of the affected device within the network architecture. The requirement for prior authentication means that while remote unauthenticated exploitation is not possible via this vector alone, it remains a critical threat for any insider actor or external attacker who has obtained valid credentials through phishing, credential stuffing, or other initial access techniques.
From an offensive security perspective, this vulnerability aligns with the ATT&CK technique T1059 Command and Scripting Interpreter, specifically under sub-techniques involving shell commands like cmd.exe on Windows or /bin/sh on Linux/Unix systems. It also relates to T1086 Service Execution if the injected command results in running a new service or process. The exploitation typically involves identifying input fields that are reflected into system calls without proper encoding, escaping, or parameterization of arguments. Defenders should recognize this as a high-severity issue requiring immediate remediation once authentication is established by an unauthorized party.
Mitigation strategies must focus on both technical fixes and procedural controls. The primary technical solution is to refactor the affected code paths to avoid direct OS command execution where possible. If system commands are necessary, developers should use language-specific APIs that accept arguments as distinct parameters rather than constructing a single string for shell parsing. This approach inherently prevents metacharacter interpretation because the operating system treats each parameter separately. Additionally, strict input validation using allow-listing techniques can help ensure that only expected character sets and formats are processed. Implementing least-privilege principles is also critical; ensuring that the application runs with minimal OS-level permissions limits the blast radius if an injection does occur. Finally, organizations should enforce strong authentication policies and monitor for anomalous command execution patterns within their industrial networks to detect potential exploitation attempts early.