CVE-2026-73749 in AOS-CX
Summary
by MITRE • 09/02/2026
Multiple vulnerabilities exist in a daemon of AOS-CX that may allow for improper processing of malformed input. An unauthenticated remote attacker could exploit these vulnerabilities by sending specially crafted packets to the affected service. Successful exploitation could result in remote code execution with elevated privileges.
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Analysis
by VulDB Data Team • 09/02/2026
The identified security issues reside within a core network operating system daemon associated with AOS-CX, representing a critical class of software defects where input validation mechanisms are insufficient or entirely absent. These vulnerabilities stem from the improper processing of malformed input data structures received by the service handler. In complex networking stacks, daemons often parse high-volume traffic to maintain routing tables, manage switch configurations, and handle control plane protocols. When these components fail to rigorously sanitize incoming packets before parsing them into internal memory structures, they create conditions ripe for exploitation. The specific nature of this flaw suggests a classic buffer overflow or heap corruption scenario, where the daemon allocates memory based on untrusted input lengths without verifying bounds, allowing an attacker to overwrite adjacent memory regions with maliciously crafted data.
The severity of these vulnerabilities is amplified by their remote and unauthenticated accessibility. An adversary does not need valid credentials or prior access to the network management plane to initiate an attack vector. By simply sending specially crafted packets over standard network protocols such as TCP, UDP, or specific control plane protocols like OSPF, BGP, or SNMP depending on which daemon is affected, a remote attacker can trigger the faulty code path. This characteristic aligns with Common Weakness Enumeration (CWE) categories such as CWE-120 Buffer Copy without Checking Size of Input and CWE-787 Out-of-bounds Write. The lack of authentication requirement places this vulnerability in the highest risk category for network-facing services, as it eliminates the barrier of credential theft or privilege escalation through brute force attacks prior to exploitation.
Successful exploitation of these flaws yields a catastrophic outcome: remote code execution with elevated privileges. This means that once the malformed packet triggers the memory corruption, the attacker gains control over the instruction pointer and can execute arbitrary commands within the context of the daemon process. Since network daemons typically run with root or system-level permissions to manage hardware interfaces and routing tables, this privilege level allows the attacker to fully compromise the host device. The operational impact extends beyond a single compromised switch; it enables lateral movement across the network infrastructure, interception of sensitive traffic through packet sniffing at the kernel level, modification of forwarding rules to facilitate man-in-the-middle attacks, or complete denial of service by crashing critical system processes. This scenario is consistent with MITRE ATT&CK techniques involving Initial Access via Network Service Exploitation and Privilege Escalation to gain administrative control over network devices.
Mitigation strategies must prioritize immediate patching through vendor-provided updates that address the input validation logic within the affected daemon. Until patches are applied, network administrators should implement strict access control lists on upstream routers or firewalls to restrict source IP addresses allowed to communicate with the vulnerable service ports. Additionally, enabling deep packet inspection features where available can help identify and block anomalous traffic patterns indicative of buffer overflow attempts. It is also critical to ensure that management interfaces are not exposed directly to untrusted networks such as the public internet, adhering to the principle of least privilege by restricting access to trusted administrative subnets only. Regular vulnerability scanning and continuous monitoring for unusual control plane activity remain essential components of a defense-in-depth strategy against these types of high-severity infrastructure vulnerabilities.