CVE-2021-1231— Cisco Nexus 9000 Series Fabric Switches ACI Mode Link Layer Discovery Protocol Port Denial of Service Vulnerability
Quick assessment
Affected
Cisco Cisco NX-OS System Software in ACI Mode
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Cisco Nexus 9000 Series Fabric Switches是美国思科（Cisco）公司的一款9000系列光纤交换机。 Nexus 9000 Series Fabri 存在访问控制错误漏洞，攻击者可利用该漏洞禁用SFP接口上的切换，这可能会中断网络。
Possible ATT&CK Techniques 3 AI
T1134 · Access Token Manipulation T1499 · Endpoint Denial of Service T1557 · Adversary-in-the-Middle
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I. Basic Information for CVE-2021-1231
Vulnerability Information
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Vulnerability Title
Cisco Nexus 9000 Series Fabric Switches ACI Mode Link Layer Discovery Protocol Port Denial of Service Vulnerability
Source: CVE Program / CVE List V5
Vulnerability Description
A vulnerability in the Link Layer Discovery Protocol (LLDP) for Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode could allow an unauthenticated, adjacent attacker to disable switching on a small form-factor pluggable (SFP) interface. This vulnerability is due to incomplete validation of the source of a received LLDP packet. An attacker could exploit this vulnerability by sending a crafted LLDP packet on an SFP interface to an affected device. A successful exploit could allow the attacker to disable switching on the SFP interface, which could disrupt network traffic.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
Source: CVE Program / CVE List V5
Vulnerability Type
访问控制不恰当
Source: CVE Program / CVE List V5
Vulnerability Title
Cisco Nexus 9000 Series Fabric 访问控制错误漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Cisco Nexus 9000 Series Fabric Switches是美国思科（Cisco）公司的一款9000系列光纤交换机。 Nexus 9000 Series Fabri 存在访问控制错误漏洞，攻击者可利用该漏洞禁用SFP接口上的切换，这可能会中断网络。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| Cisco | Cisco NX-OS System Software in ACI Mode | n/a | - |
|
II. Public POCs for CVE-2021-1231
| # | POC Description | Source Link | Shenlong Link |
|---|
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Vendor Advisories for CVE-2021-1231 (1)
-
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apic-lldap-dos-WerV9CFj vendor-advisory x_refsource_CISCO
Same Patch Batch · Cisco · 2021-02-24 · 13 CVEs total
| CVE-2021-1388 | 10.0 CRITICAL | Cisco ACI Multi-Site Orchestrator Application Services Engine Deployment Authentication By |
| CVE-2021-1361 | 9.8 CRITICAL | Cisco NX-OS Software Unauthenticated Arbitrary File Actions Vulnerability |
| CVE-2021-1393 | 9.8 CRITICAL | Cisco Application Services Engine Unauthorized Access Vulnerabilities |
| CVE-2021-1396 | 9.8 CRITICAL | Cisco Application Services Engine Unauthorized Access Vulnerabilities |
| CVE-2021-1368 | 8.8 HIGH | Cisco FXOS and NX-OS Software Unidirectional Link Detection Denial of Service and Arbitrar |
| CVE-2021-1230 | 8.6 HIGH | Cisco Nexus 9000 Series Fabric Switches ACI Mode BGP Route Installation Denial of Service |
| CVE-2021-1387 | 8.6 HIGH | Cisco NX-OS Software IPv6 Netstack Denial of Service Vulnerability |
| CVE-2021-1228 | 7.4 HIGH | Cisco Nexus 9000 Series Fabric Switches ACI Mode Fabric Infrastructure VLAN Unauthorized A |
| CVE-2021-1229 | 5.8 MEDIUM | Cisco NX-OS Software ICMP Version 6 Memory Leak Denial of Service Vulnerability |
| CVE-2021-1450 | 5.5 MEDIUM | Cisco AnyConnect Secure Mobility Client Denial of Service Vulnerability |
| CVE-2021-1367 | 4.3 MEDIUM | Cisco NX-OS Software Protocol Independent Multicast Denial of Service Vulnerability |
| CVE-2021-1227 | Cisco NX-OS Software NX-API Cross-Site Request Forgery Vulnerability |
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V. Comments for CVE-2021-1231
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