CVE-2021-3455 json
Disconnecting L2CAP channel right after invalid ATT request leads freeze
published 2021-10-19 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-26778
- cvss
- 4.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.1%
- EPSS 1.1% chance of exploitation in 30 days, percentile 66%
- public exploits
- 0
- none known
Summary
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
Patch / fix
- zephyrproject zephyr 2.6.0
Exploit prediction
1.11% chance of exploitation in the next 30 days, higher than 66% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com http://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-7g38-3x9v-v7vp referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 4.3 | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
Affected products
- zephyrproject-rtos zephyr
Classification
- Weakness
-
- CWE-416 Use After Free
References
-
github.com
/zephyrproject-rtos/zephyr/security/advisories/GHSA-7g38-3x9v-v7vp
exploit, third-party-advisory
Sources
- CVE List CVE-2021-3455
- NVD CVE-2021-3455
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