Cisco
CVE-2026-20010
HIGH
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
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AccessCraft malicious LLDP frame with invalid fields
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DeliverySend packet to target device interface
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ExploitTrigger improper field parsing in LLDP process
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ExecutionLLDP process crashes and restarts
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ImpactDevice reloads causing denial of service
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2021 - Vulnerable and Outdated Components
ASVS 5.0
V15 - Secure Coding and Architecture Buffer access bounds checking
|
| Exploitation Conditions | LLDP feature must be enabled on target Cisco NX-OS device interface. Attacker must have network access to Layer 2 adjacent network segment where target device is connected. |
| Impact | CVSS 7.4 (HIGH). Attack vector: Adjacent Network. Complexity: Low. Privileges required: None. User interaction: None. Exploitation no authentication required. |
| Exploit ScenarioDerived | An attacker without authentication could exploit this vulnerability to cause the device to reload, resulting in a denial of service (DoS) condition. |
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Alert meAnalysisAIv1 – Mar 12, 2026
Cisco NX-OS devices can be forced to reload through a crafted LLDP packet sent by an adjacent, unauthenticated attacker, causing a denial of service condition. The vulnerability stems from improper frame field validation in the LLDP process, exploitable only from directly connected network segments. No patch is currently available for affected systems.
Earlier versions of this analysis (1)
A vulnerability in the Link Layer Discovery Protocol (LLDP) feature of Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause the LLDP process to restart, which could cause an affected device to reload unexpectedly. [CVSS 7.4 HIGH]
RemediationAI
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Affected ProductsAI
Component: a denial of.
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Technical ContextAI · show details
exists in the a denial of component. in the Link Layer Discovery Protocol (LLDP) feature of Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause the LLDP process to restart, which could cause an affected device to reload unexpectedly.
This vulnerability is due to improper handling of specific fields in an LLDP frame. An attacker could exploit this vulnerability by sending a crafted LLDP packet to an interface of an affected device. A successful exploit could allow the attacker to cause the device to re
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Severity by source
AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
A vulnerability in the Link Layer Discovery Protocol (LLDP) feature of Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause the LLDP process to restart, which could cause an affected device to reload unexpectedly.
This vulnerability is due to improper handling of specific fields in an LLDP frame. An attacker could exploit this vulnerability by sending a crafted LLDP packet to an interface of an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition. Note: LLDP is a Layer 2 link protocol. To exploit this vulnerability, an attacker would need to be directly connected to an interface of an affected device, either physically or logically (for example, through a Layer 2 Tunnel configured to transport the LLDP protocol).
Executive ViewAI
Cisco NX-OS devices are vulnerable to a denial-of-service attack from adjacent network attackers that can force unexpected device reloads. This affects network infrastructure availability and could disrupt critical operations if exploited on production switches or routers.
Disable LLDP feature where operationally feasible; restrict LLDP to trusted network segments only; implement network access controls (802.1X) to prevent untrusted adjacent device connections; enable SNMP traps for process restarts to detect exploitation attempts; schedule device reloads during maintenance windows to limit business impact if exploited.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
GitHub PoC
Exploit-DB