CVE-2026-76499 in Application Policy Infrastructure Controller
Summary
by MITRE • 10/07/2026
As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Application Policy Infrastructure Controller (APIC) engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.
The vulnerabilities tracked by CVE-2026-76499 are related to improper neutralization issues that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-707.
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Analysis
by VulDB Data Team • 10/07/2026
Cisco has released software hardening updates for the Application Policy Infrastructure Controller, commonly known as APIC, following a comprehensive internal security review aimed at enhancing product quality and proactive defense capabilities. This initiative addresses multiple vulnerabilities discovered during rigorous testing processes within the engineering team. The primary focus of these remediation efforts is on CVE-2026-76499, which represents a critical flaw in how input data is processed by the controller software. By addressing this issue, Cisco aims to prevent potential exploitation that could compromise the integrity and availability of network infrastructure managed through APIC.
The technical nature of CVE-2026-76499 centers on improper neutralization of special elements used in a command, which falls under the Common Weakness Enumeration category CWE-707. This specific weakness occurs when software fails to properly validate or sanitize user-supplied input before using it in commands that interact with an operating system or other components. In the context of APIC, this could allow an attacker who has access to certain interfaces or APIs to inject malicious command sequences. The lack of proper neutralization means that special characters or syntax intended for structural purposes within a command are interpreted as executable instructions rather than literal data. This fundamental flaw bypasses expected security controls and allows for unauthorized execution of system-level commands.
The operational impact of this vulnerability is significant due to the central role APIC plays in software-defined networking environments. As the management plane for Cisco ACI fabrics, APIC handles configuration policies, monitoring data, and administrative functions across multiple nodes. If an attacker successfully exploits improper neutralization issues categorized under CWE-707, they could potentially execute arbitrary commands with the privileges of the application process. This level of access enables a wide range of malicious activities, including but not limited to privilege escalation, data exfiltration, or complete system compromise. Such exploitation undermines the confidentiality, integrity, and availability guarantees provided by secure network architectures. Attackers might leverage this flaw to modify routing policies, disrupt traffic flow, or install persistent backdoors within the infrastructure management layer.
Mitigation strategies primarily involve applying the software hardening releases issued by Cisco as part of their proactive security commitment. Administrators should prioritize updating APIC instances to the patched versions that address these specific internal findings. Beyond immediate patching, organizations are advised to review access controls and ensure that only authorized personnel have administrative privileges over APIC interfaces. Implementing strict input validation mechanisms at application boundaries can further reduce exposure to similar CWE-707 vulnerabilities in future developments. Additionally, monitoring logs for unusual command execution patterns or unexpected system behavior provides an additional layer of defense against potential exploitation attempts. Aligning with industry standards such as MITRE ATT&CK techniques related to command and script interpretation helps security teams anticipate attack vectors and strengthen detection capabilities around these critical infrastructure components.