Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2021-27862— L2 network filtering bypass using stacked VLAN0 and LLC/SNAP headers with an invalid length during Ethernet to Wifi frame translation

Quick assessment

Affected
IEEE 802.2
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等都是美国思科（Cisco）公司的产品。Cisco NX-OS Software是一套交换机使用的数据中心级操作系统软件。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 IOS Software - Switches、Cisco IOS XE Software - Switches、Cisco IOS XE Software - Routers、Cisco IOS XR Software、C

AI Predicted 5.3 Difficulty: Moderate EPSS 0.69% · P51

Possible ATT&CK Techniques 1 AI

T1557 · Adversary-in-the-Middle
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2021-27862

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
L2 network filtering bypass using stacked VLAN0 and LLC/SNAP headers with an invalid length during Ethernet to Wifi frame translation
Source: CVE Program / CVE List V5
Vulnerability Description
Layer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using LLC/SNAP headers with invalid length and Ethernet to Wifi frame conversion (and optionally VLAN0 headers).
Source: CVE Program / CVE List V5
CVSS Information
N/A
Source: CVE Program / CVE List V5
Vulnerability Type
长度参数不一致性处理不恰当
Source: CVE Program / CVE List V5
Vulnerability Title
多款Cisco产品安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Cisco NX-OS Software等都是美国思科（Cisco）公司的产品。Cisco NX-OS Software是一套交换机使用的数据中心级操作系统软件。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 IOS Software - Switches、Cisco IOS XE Software - Switches、Cisco IOS XE Software - Routers、Cisco IOS XR Software、C
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
IEEE 802.2 802.2h-1997 ~ 802.2h-1997 -
IETF draft-ietf-v6ops-ra-guard-08 08 ~ 08 -

II. Public POCs for CVE-2021-27862

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2021-27862

请登录查看更多情报信息。

Vendor Advisories for CVE-2021-27862 (1)

Security Blog Posts for CVE-2021-27862 (1)

Other References for CVE-2021-27862 (2)

Same Patch Batch · IEEE · 2022-09-27 · 3 CVEs total

CVE-2021-27853 L2 network filtering can be bypassed using stacked VLAN0 and LLC/SNAP headers
CVE-2021-27861 L2 network filtering bypass using stacked VLAN0 and LLC/SNAP headers with invalid lengths

IV. Related Vulnerabilities

Same product: 802.2
Same vendor: IEEE
Same weakness: CWE-130

V. Comments for CVE-2021-27862

No comments yet

Leave a comment