CVE-2020-3421— Cisco IOS XE Software Zone-Based Firewall Denial of Service Vulnerabilities
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I. Basic Information for CVE-2020-3421
Vulnerability Information
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Vulnerability Title
Cisco IOS XE Software Zone-Based Firewall Denial of Service Vulnerabilities
Source: NVD (National Vulnerability Database)
Vulnerability Description
Multiple vulnerabilities in the Zone-Based Firewall feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the device to reload or stop forwarding traffic through the firewall. The vulnerabilities are due to incomplete handling of Layer 4 packets through the device. An attacker could exploit these vulnerabilities by sending a certain sequence of traffic patterns through the device. A successful exploit could allow the attacker to cause the device to reload or stop forwarding traffic through the firewall, resulting in a denial of service. For more information about these vulnerabilities, see the Details section of this advisory.
Source: NVD (National Vulnerability Database)
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Source: NVD (National Vulnerability Database)
Vulnerability Type
对因果或异常条件的不恰当检查
Source: NVD (National Vulnerability Database)
Vulnerability Title
Cisco IOS XE Software Zone-Based Firewall 代码问题漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Cisco IOS和IOS XE都是美国思科（Cisco）公司的产品。CLI是其中的一个命令行界面。 Cisco IOS XE Software Zone-Based Firewall feature中存在安全漏洞，该漏洞源于未通过设备处理第4层数据包引起的，该漏洞允许攻击者可以通过设备发送一定顺序的流量模式来利用这些漏洞。
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 IOS XE Software | n/a | - |
II. Public POCs for CVE-2020-3421
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|---|
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- Cisco IOS XE Software Zone-Based Firewall Denial of Service Vulnerabilitiesvendor-advisoryx_refsource_CISCO
- https://nvd.nist.gov/vuln/detail/CVE-2020-3421
Same Patch Batch · Cisco · 2020-09-24 · 52 CVEs total
| CVE-2020-3141 | 8.8 HIGH | Cisco IOS XE Software Privilege Escalation Vulnerabilities |
| CVE-2020-3425 | 8.8 HIGH | Cisco IOS XE Software Privilege Escalation Vulnerabilities |
| CVE-2020-3480 | 8.6 HIGH | Cisco IOS XE Software Zone-Based Firewall Denial of Service Vulnerabilities |
| CVE-2020-3399 | 8.6 HIGH | Cisco IOS XE Wireless Controller Software for the Catalyst 9000 Family CAPWAP Denial of Se |
| CVE-2020-3426 | 7.5 HIGH | Cisco IOS Software for Cisco Industrial Routers Virtual-LPWA Unauthorized Access Vulnera |
| CVE-2020-3508 | 7.4 HIGH | Cisco IOS XE Software for Cisco ASR 1000 Series 20-Gbps Embedded Services Processor IP ARP |
| CVE-2020-3465 | 7.4 HIGH | Cisco IOS XE Software Ethernet Frame Denial of Service Vulnerability |
| CVE-2020-3396 | 6.8 MEDIUM | Cisco IOS XE Software IOx Guest Shell USB SSD Namespace Protection Privilege Escalation Vu |
| CVE-2020-3417 | 6.8 MEDIUM | Cisco IOS XE Software Arbitrary Code Execution Vulnerability |
| CVE-2020-3513 | 6.7 MEDIUM | Cisco IOS XE Software for Cisco ASR 900 Series Route Switch Processor 3 Arbitrary Code Exe |
| CVE-2020-3416 | 6.7 MEDIUM | Cisco IOS XE Software for Cisco ASR 900 Series Route Switch Processor 3 Arbitrary Code Exe |
| CVE-2020-3479 | 6.1 MEDIUM | Cisco IOS and IOS XE Software MP-BGP EVPN Denial of Service Vulnerability |
| CVE-2020-3393 | 6.0 MEDIUM | Cisco IOS XE Software IOx Application Hosting Privilege Escalation Vulnerability |
| CVE-2020-3503 | 6.0 MEDIUM | Cisco IOS XE Software Guest Shell Unauthorized File System Access Vulnerability |
| CVE-2020-3423 | 5.1 MEDIUM | Cisco IOS XE Software Arbitrary Code Execution Vulnerability |
| CVE-2020-3474 | 4.3 MEDIUM | Cisco IOS XE Software Web Management Framework Vulnerabilities |
| CVE-2020-3475 | 4.3 MEDIUM | Cisco IOS XE Software Web Management Framework Vulnerabilities |
| CVE-2020-3422 | Cisco IOS XE Software IP Service Level Agreements Denial of Service Vulnerability | |
| CVE-2020-3476 | Cisco IOS XE Software Arbitrary File Overwrite Vulnerability | |
| CVE-2020-3428 | Cisco IOS XE Wireless Controller Software for the Catalyst 9000 Family WLAN Local Profilin |
Showing top 20 of 52 CVEs. View all on vendor page → →
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V. Comments for CVE-2020-3421
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