CVE-2021-3455

4.3 MEDIUM

Disconnecting L2CAP channel right after invalid ATT request leads freeze

Published: 2021-10-19 · Last updated: 2026-06-17

Severity and scoring

CVSS: 4.3 MEDIUM
Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CWE: CWE-416

Affected products

Vendor	Product
zephyrproject	zephyr

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: NVD

References

[NVD]https://nvd.nist.gov/vuln/detail/CVE-2021-3455
[Exploit reference]http://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-7g38-3x9v-v7vp
[Exploit reference]http://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-7g38-3x9v-v7vp

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