CVE-2021-27853— L2 network filtering can be bypassed using stacked VLAN0 and LLC/SNAP headers
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I. Basic Information for CVE-2021-27853
Vulnerability Information
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Vulnerability Title
L2 network filtering can be bypassed using stacked VLAN0 and LLC/SNAP headers
Source: NVD (National Vulnerability Database)
Vulnerability Description
Layer 2 network filtering capabilities such as IPv6 RA guard or ARP inspection can be bypassed using combinations of VLAN 0 headers and LLC/SNAP headers.
Source: NVD (National Vulnerability Database)
CVSS Information
N/A
Source: NVD (National Vulnerability Database)
Vulnerability Type
使用欺骗进行的认证绕过
Source: NVD (National Vulnerability Database)
Vulnerability Title
多款Cisco产品安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Cisco IOS等都是美国思科（Cisco）公司的产品。Cisco IOS是一套为其网络设备开发的操作系统。Cisco IOS XE Software是一个操作系统。Cisco Small Business是一个交换机。 Cisco IOS Software - Switches、Cisco IOS XE Software - Switches、Cisco IOS XE Software - Routers、Cisco IOS XR Software、Cisco Meraki - Switches、Ci
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
II. Public POCs for CVE-2021-27853
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Same Patch Batch · IEEE · 2022-09-27 · 3 CVEs total
| CVE-2021-27861 | L2 network filtering bypass using stacked VLAN0 and LLC/SNAP headers with invalid lengths | |
| CVE-2021-27862 | L2 network filtering bypass using stacked VLAN0 and LLC/SNAP headers with an invalid lengt |
IV. Related Vulnerabilities
Same vendor: IEEE
- CVE-2021-27862
L2 network filtering bypass using stacked VLAN0 and LLC/SNAP - CVE-2021-27861
L2 network filtering bypass using stacked VLAN0 and LLC/SNAP - CVE-2017-13091
The P1735 IEEE standard describes flawed methods for encrypt - CVE-2017-13092
The P1735 IEEE standard describes flawed methods for encrypt - CVE-2017-13093
The P1735 IEEE standard describes flawed methods for encrypt
Same weakness: CWE-290
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V. Comments for CVE-2021-27853
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