CVE-2021-1387— Cisco NX-OS Software IPv6 Netstack Denial of Service Vulnerability
Quick assessment
Affected
Cisco Cisco NX-OS Software
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 NX-OS Software是美国思科（Cisco）公司的一套交换机使用的数据中心级操作系统软件。 Cisco NX-OS Software 存在安全漏洞，该漏洞允许未经身份验证的远程攻击者可利用该漏洞在受影响的设备上造成拒绝服务。
Possible ATT&CK Techniques 2 AI
T1499.004 · Application or System Exploitation T1499.001 · OS Exhaustion Flood
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I. Basic Information for CVE-2021-1387
Vulnerability Information
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Vulnerability Title
Cisco NX-OS Software IPv6 Netstack Denial of Service Vulnerability
Source: CVE Program / CVE List V5
Vulnerability Description
A vulnerability in the network stack of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability exists because the software improperly releases resources when it processes certain IPv6 packets that are destined to an affected device. An attacker could exploit this vulnerability by sending multiple crafted IPv6 packets to an affected device. A successful exploit could cause the network stack to run out of available buffers, impairing operations of control plane and management plane protocols and resulting in a DoS condition. Manual intervention would be required to restore normal operations on the affected device. For more information about the impact of this vulnerability, see the Details section of this advisory.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
在移除最后引用时对内存的释放不恰当(内存泄露)
Source: CVE Program / CVE List V5
Vulnerability Title
Cisco NX-OS Software 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Cisco NX-OS Software是美国思科（Cisco）公司的一套交换机使用的数据中心级操作系统软件。 Cisco NX-OS Software 存在安全漏洞，该漏洞允许未经身份验证的远程攻击者可利用该漏洞在受影响的设备上造成拒绝服务。
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 Software | n/a | - |
|
II. Public POCs for CVE-2021-1387
| # | POC Description | Source Link | Shenlong Link |
|---|
AI-Generated POC
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Vendor Advisories for CVE-2021-1387 (1)
-
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nxos-ipv6-netstack-edXPGV7K 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-2021-1228 | 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-2021-1231 | 4.7 MEDIUM | Cisco Nexus 9000 Series Fabric Switches ACI Mode Link Layer Discovery Protocol Port Denial |
| 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-2021-1387
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