CVE-2026-6505 in AXIS OS
Summary
by MITRE • 08/11/2026
The ACAP framework contains a Time-of-Check to Time-of-Use (TOCTOU) race condition, which could potentially lead to privilege escalation. This vulnerability can only be exploited if the Axis device is configured to allow the installation of unsigned ACAP applications, and if an attacker convinces the victim to install a malicious ACAP application.
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Analysis
by VulDB Data Team • 08/11/2026
The ACAP framework vulnerability represents a critical time-of-check to time-of-use race condition that undermines the security posture of Axis network devices. This flaw exists within the application installation process where the system performs initial validation checks at one point in time but subsequently uses different system states before completing the operation. The vulnerability stems from the framework's failure to maintain consistent state validation throughout the installation lifecycle, creating an exploitable window where malicious actors can manipulate the environment between verification and execution phases.
The technical implementation of this race condition manifests when unsigned ACAP applications are permitted on Axis devices, as the system's security controls become insufficient to prevent unauthorized installations. The attacker must first establish a scenario where the device configuration allows unsigned application installation, typically through administrative settings that disable code signing requirements or enable developer modes. Once this precondition is met, the malicious actor can craft an application that exploits the timing gap between when the system validates installation permissions and when it actually executes the application code.
The operational impact of this vulnerability extends beyond simple privilege escalation to potentially compromise entire network infrastructures. When successfully exploited, the TOCTOU race condition enables attackers to gain elevated privileges that would normally be restricted, allowing them to execute arbitrary code with administrative rights on the affected devices. This privilege escalation capability can lead to persistent access, data exfiltration, and further lateral movement within network environments where Axis devices serve as critical infrastructure components.
The vulnerability's exploitation requires social engineering elements as attackers must convince victims to install malicious applications, making it a hybrid threat that combines technical flaws with human factors. This characteristic aligns with ATT&CK technique T1059 for execution and T1546 for privilege escalation, while the underlying race condition falls under CWE-367 which specifically addresses time-of-check to time-of-use vulnerabilities. The configuration dependency on unsigned application installation settings creates a vector that can be mitigated through proper device hardening practices.
Mitigation strategies should focus on eliminating the conditions that enable exploitation while maintaining operational functionality. Device administrators must enforce strict code signing policies and disable unsigned application installation capabilities unless absolutely required for legitimate development purposes. Network segmentation and monitoring solutions should detect unusual application installation patterns, while regular security audits can identify misconfigured devices that permit such vulnerabilities. The recommended approach includes implementing automated compliance checks to ensure that only signed applications are installed and that the system maintains consistent state validation throughout all phases of the installation process.
Security controls should also address the social engineering aspects by providing user education on application installation risks and establishing clear policies for software deployment. The vulnerability demonstrates how seemingly minor configuration oversights can create significant security gaps, emphasizing the importance of comprehensive risk assessment and proper security configuration management in network infrastructure devices. Organizations should implement continuous monitoring to detect unauthorized changes to application installation policies and maintain up-to-date threat intelligence regarding similar vulnerabilities in industrial control systems.
The TOCTOU race condition within ACAP framework represents a fundamental flaw in state management that requires immediate attention through both technical remediation and operational policy changes. The vulnerability's potential for privilege escalation makes it particularly dangerous in environments where Axis devices control critical network infrastructure, requiring organizations to implement layered security approaches that address both the technical implementation gaps and the human factors that enable exploitation.