CVE-2026-18461 in Connext Professional
Summary
by MITRE • 09/22/2026
Use of Externally-Controlled Format String vulnerability in RTI Connext Professional (Core Libraries) allows Format String Injection. This issue affects Connext Professional: from 7.5.0 before 7.7.0.1, from 7.3.0.10 before 7.3.1.6.
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Analysis
by VulDB Data Team • 09/22/2026
The vulnerability identified as a use of externally-controlled format string in RTI Connext Professional Core Libraries represents a critical security flaw that enables attackers to perform format string injection attacks. This type of vulnerability arises when an application accepts user-supplied input and passes it directly into formatting functions, such as printf or similar logging mechanisms, without proper sanitization or validation. In the context of Real-Time Interprocess Communication (RTI) Connext Professional, which is widely used in safety-critical systems for reliable data exchange between distributed components, this flaw poses a significant risk to system integrity and availability. The affected versions include releases from 7.5.0 up to but not including 7.7.0.1, as well as the maintenance release series starting from 7.3.0.10 up to but excluding 7.3.1.6. These version ranges indicate that the issue has persisted across multiple major and minor releases, suggesting a systemic oversight in input handling within specific code paths of the core libraries.
From a technical perspective, format string vulnerabilities occur when an attacker can control the format specifier passed to a function like printf. By injecting special characters such as %x or %n into log messages or debug outputs, an adversary can read arbitrary memory contents from the stack or heap, leading to information disclosure. More dangerously, using write specifiers like %n allows for writing data to specific memory addresses, which can result in arbitrary code execution if the attacker can predict memory layout and control pointers. In distributed systems relying on RTI Connext, where nodes communicate over networks, an attacker who gains access to a compromised node or intercepts network traffic could exploit this flaw remotely. The impact extends beyond simple data leakage; it undermines the confidentiality, integrity, and availability of the entire communication infrastructure, potentially allowing remote code execution with the privileges of the vulnerable process.
This vulnerability aligns closely with Common Weakness Enumeration (CWE) ID 134, which defines Use of Externally-Controlled Format String. It also maps to MITRE ATT&CK techniques related to input validation failures and potential exploitation paths for privilege escalation or remote code execution. The operational impact is severe because RTI Connext is often deployed in environments requiring high reliability and security, such as industrial control systems, aerospace applications, and automotive software. A successful exploit could allow an attacker to disrupt real-time communications, inject malicious commands into the system logic, or pivot through connected nodes by leveraging the elevated privileges typically held by middleware processes. The persistence of this issue across multiple versions highlights the importance of rigorous code review practices and automated static analysis tools that specifically target format string misuse in C/C++ based software ecosystems.
Mitigation strategies must prioritize immediate patching to the latest secure version within the supported release lines, ensuring that users upgrade to at least 7.3.1.6 or 7.7.0.1 depending on their current deployment baseline. For organizations unable to immediately update due to certification or compatibility constraints, defensive coding practices should be enforced in any custom extensions or wrappers around the core libraries. This includes strictly validating all input strings before they are passed to logging functions and ensuring that user-controlled data is never used as a format string argument. Additionally, enabling compiler warnings for format string issues and utilizing static analysis tools during the development lifecycle can help detect such flaws early. Network segmentation and strict access controls further reduce the attack surface by limiting who can interact with the Connext infrastructure, thereby mitigating the risk of remote exploitation even if the underlying vulnerability remains present in older versions.