CVE-2021-3455— Disconnecting L2CAP channel right after invalid ATT request leads freeze
Quick assessment
Affected
zephyrproject-rtos zephyr
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.
Zephyr是美国Linux基金会的一套开源的小型的可缩放的实时操作系统。 Zephyr 2.4.0及更高版本，2.5.0及更高版本存在资源管理错误漏洞，该漏洞源于在无效ATT请求导致冻结后立即断开L2CAP通道。更多信息，请参见https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-7g38-3x9v-v7vp。
Possible ATT&CK Techniques 1 AI
T1190 · Exploit Public-Facing Application
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I. Basic Information for CVE-2021-3455
Vulnerability Information
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Vulnerability Title
Disconnecting L2CAP channel right after invalid ATT request leads freeze
Source: CVE Program / CVE List V5
Vulnerability Description
Disconnecting L2CAP channel right after invalid ATT request leads freeze. Zephyr versions >= 2.4.0, >= 2.5.0 contain Use After Free (CWE-416). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-7g38-3x9v-v7vp
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Source: CVE Program / CVE List V5
Vulnerability Type
释放后使用
Source: CVE Program / CVE List V5
Vulnerability Title
Zephyr 资源管理错误漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Zephyr是美国Linux基金会的一套开源的小型的可缩放的实时操作系统。 Zephyr 2.4.0及更高版本，2.5.0及更高版本存在资源管理错误漏洞，该漏洞源于在无效ATT请求导致冻结后立即断开L2CAP通道。更多信息，请参见https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-7g38-3x9v-v7vp。
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 |
|---|---|---|---|---|
| zephyrproject-rtos | zephyr | 2.4.0 ~ unspecified | - |
|
II. Public POCs for CVE-2021-3455
| # | POC Description | Source Link | Shenlong Link |
|---|
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Vendor Advisories for CVE-2021-3455 (1)
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V. Comments for CVE-2021-3455
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