Description

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.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.5",
  "pubDate": "2026-08-18T19:16:45.980Z",
  "pubdate": "2026-08-18T19:16:45.980Z",
  "executiveSummary": "A buffer overflow vulnerability exists within the Link Layer Discovery Protocol (LLDP) daemon component of NVIDIA Cumulus Linux. This security flaw allows an unauthenticated adversary positioned on an adjacent network to execute arbitrary code by transmitting maliciously crafted LLDP frames to the target system. The primary impact of successful exploitation includes remote code execution, potentially compromising the integrity, confidentiality, and availability of the affected networking device. Because the attack vector resides at the data link layer, unauthorized actors with direct physical or logical adjacency can trigger the vulnerability without possessing prior credentials or interacting with authentication mechanisms. The risk implications are severe, as network infrastructure devices often serve as critical control points within enterprise and data center architectures. Exploitation requirements are strictly limited to network adjacency and the ability to inject crafted frames into the local broadcast domain where LLDP operates. No user interaction or prior system access is required, elevating the overall severity and necessitating immediate remediation through available patches or operational workarounds provided by the vendor.",
  "technicalDetails": "The vulnerability resides in the Link Layer Discovery Protocol (LLDP) daemon component responsible for parsing and processing incoming LLDP data units within NVIDIA Cumulus Linux. The root cause stems from insufficient bounds checking and memory validation when handling specific Type-Length-Value (TLV) fields or frame attributes contained within incoming LLDP frames. When the vulnerable daemon parses a specially crafted LLDP payload, the excessive data overflows the allocated memory buffer on the stack or heap, corrupting adjacent memory structures and potentially hijacking the execution flow.\nThe attack flow proceeds as follows: First, the unauthenticated attacker establishes a presence on the adjacent network segment, granting direct Layer 2 connectivity to the target NVIDIA Cumulus Linux device. Second, the adversary crafts malicious LLDP frames containing oversized or malformed payloads designed to exceed the internal buffer capacity of the LLDP daemon parser. Third, the attacker transmits these frames onto the local network segment. Fourth, the targeted device captures and processes the frames via the LLDP daemon component. Fifth, upon parsing the malicious input, the lack of proper length validation results in a buffer overflow condition. Finally, if the payload is meticulously engineered, the overwritten instruction pointer or function pointers lead to arbitrary code execution with the privileges of the LLDP daemon.\nThe vulnerable component is the LLDP daemon responsible for handling Link Layer Discovery Protocol communications. The affected software is NVIDIA Cumulus Linux. Network exposure is restricted to the adjacent network due to the non-routable nature of LLDP traffic, which operates at Layer 2 of the OSI model. Authentication requirements are nonexistent, as LLDP is an unauthenticated protocol by design. Privilege requirements for the attacker are minimal, requiring only local network access to transmit frames into the broadcast domain. The post-exploitation impact includes full code execution on the networking device, which could allow the adversary to establish persistence, pivot deeper into the internal network, intercept transit traffic, or disrupt critical network operations."
}