CVE-2026-24184 in Cumulus Linux
Summary
by MITRE • 08/18/2026
NVIDIA Cumulus Linux contains a vulnerability in the Link Layer Discovery Protocol (LLDP) daemon component, where an unauthenticated attacker on an adjacent network could cause buffer overflow by sending crafted LLDP frames. A successful exploit of this vulnerability might lead to code execution.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 08/18/2026
The NVIDIA Cumulus Linux operating system, widely deployed in high-performance data center and cloud infrastructure environments, contains a critical security flaw within its Link Layer Discovery Protocol daemon component. This vulnerability stems from an improper handling of incoming LLDP frames, specifically resulting in a buffer overflow condition when processing crafted or malformed packets. The Link Layer Discovery Protocol is a vendor-neutral media access control layer protocol used by network devices to advertise their identity, capabilities, and neighbors on the local area network segment. Because this protocol operates at the data link layer, it does not require authentication for basic discovery functions, making it an attractive attack vector for adversaries seeking lateral movement or initial footholds within trusted network segments that are typically isolated from direct internet exposure but accessible to adjacent networks or compromised hosts.
The technical nature of this flaw involves a buffer overflow, which occurs when the LLDP daemon writes more data into a fixed-size memory buffer than it can hold due to insufficient bounds checking on input parameters derived from maliciously crafted LLDP frames. This architectural weakness allows an unauthenticated attacker positioned on an adjacent network segment to inject specially constructed packets that exploit this boundary violation. By carefully crafting these frames, the attacker can overwrite adjacent memory locations, potentially overwriting return addresses or function pointers within the daemon process. Such manipulation of control flow is a classic precursor to arbitrary code execution, allowing the adversary to execute malicious commands with the privileges of the affected service account, which often runs with elevated permissions necessary for network management tasks.
The operational impact of this vulnerability is severe due to its potential for remote code execution without authentication. An attacker who successfully exploits this buffer overflow could gain complete control over the underlying Cumulus Linux instance or specific services running within it. In a data center context, where Cumulus Linux serves as the backbone for virtualization platforms and container orchestration systems like Kubernetes, compromising these nodes can lead to broader infrastructure compromise. This includes the potential exfiltration of sensitive configuration data, interception of network traffic through man-in-the-middle attacks facilitated by compromised routing decisions, or using the node as a pivot point to attack other critical assets within the internal network topology. The lack of authentication requirement significantly lowers the barrier for entry, enabling automated scanning and exploitation tools to target vulnerable systems across large networks efficiently.
From a classification perspective, this vulnerability aligns with CWE-120, Buffer Copy without Checking Size of Input, which describes the fundamental error in memory management that leads to buffer overflows. Furthermore, its exploitability characteristics map closely to MITRE ATT&CK techniques related to Initial Access and Execution via network services, specifically highlighting how protocols designed for benign discovery can be weaponized for malicious purposes. The vulnerability underscores the risks associated with enabling legacy or low-level networking protocols in modern infrastructure without adequate input validation mechanisms.
Mitigation strategies must prioritize immediate patching of the Cumulus Linux installation to the latest version provided by NVIDIA, which includes fixes for this LLDP daemon flaw. In environments where updating is not immediately feasible, network segmentation should be enforced to restrict access to adjacent networks that might host potential attackers. Additionally, deploying intrusion detection systems configured with signatures capable of identifying malformed LLDP packets can provide an additional layer of defense. Administrators should also consider disabling the LLDP service on interfaces where it is not strictly required for operational purposes, thereby reducing the attack surface available to unauthenticated actors seeking to exploit this specific daemon component.