Description

A signature verification bypass vulnerability exists in the command line interface of AOS-CX. Successful exploitation could allow an authenticated malicious actor with administrative privileges to execute arbitrary code on the underlying operating system, when certain pre-conditions outside of the attacker’s control are met.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.9",
  "pubDate": "2026-09-01T21:18:44.410Z",
  "pubdate": "2026-09-01T21:18:44.410Z",
  "executiveSummary": "A signature verification bypass vulnerability exists within the command line interface (CLI) of the AOS-CX network operating system. This flaw allows an authenticated user possessing administrative privileges to circumvent existing cryptographic integrity controls. By bypassing these checks, the attacker can execute arbitrary code on the underlying host operating system.\nThe vulnerability is primarily categorized as an authentication or integrity control bypass. The successful exploitation requires a pre-existing authenticated session with administrative access, significantly narrowing the attack surface to malicious insiders or compromised administrative accounts. Despite the requirement for administrative privileges, the ability to escape the CLI sandbox and execute OS-level commands represents a critical escalation of privilege.\nThe impact includes total compromise of the affected AOS-CX device, potential persistence mechanisms, and the ability to pivot within the network. This risk is compounded by the fact that the exploit relies on specific environmental pre-conditions outside of the attacker's direct control, which may serve as a secondary gate. Organizations relying on AOS-CX must prioritize limiting administrative access and monitoring CLI activity for unauthorized command patterns.",
  "technicalDetails": "The core issue resides in the AOS-CX Command Line Interface (CLI) processing engine, which fails to strictly enforce signature verification on specific administrative inputs or configuration file loads. In an environment where code or command execution is predicated on digital signature validation, the bypass allows the system to process unverified or maliciously crafted inputs as if they were cryptographically signed and trusted.\nThe attack flow commences with the attacker establishing a legitimate management session with administrative credentials. Once authenticated, the attacker interacts with specific CLI sub-systems that facilitate file operations or script execution. The vulnerability is triggered when the CLI parsing logic fails to validate the signature of the target payload against the expected trust store. Because the verification mechanism is bypassed, the underlying OS processes the input as a trusted command or binary.\nExploitation proceeds through the following phases: 1. Authentication: The attacker gains access via SSH or console with admin-level credentials. 2. Triggering: The attacker invokes specific CLI commands that engage the vulnerable verification sub-routine. 3. Payload Delivery: The attacker provides a payload, such as a malicious script or configuration file, which lacks valid cryptographic signing. 4. Bypass: The vulnerable component ignores the missing or invalid signature due to an error in the logic flow or a failure to implement the check across all entry points. 5. Execution: The underlying OS environment executes the payload with elevated privileges, bypassing the intended sandbox restrictions of the AOS-CX shell.\nThe post-exploitation impact allows for arbitrary code execution on the underlying host operating system. This enables the attacker to install backdoors, modify routing tables, intercept traffic, or exfiltrate sensitive data from the switch management plane. Because this occurs at the OS level, the attacker may be able to manipulate system logs or alter binary integrity to hide their presence. The requirement for specific pre-conditions likely refers to system states, such as specific internal service availability or hardware-specific configurations, which must align to ensure the exploit succeeds without causing system instability or crashes. The flaw highlights a breakdown in the trust chain between the CLI user interface and the underlying OS kernel or system services, specifically where inputs are passed through internal IPC (Inter-Process Communication) mechanisms without rigorous secondary validation."
}