CVE-2021-3436
BT: Possible to overwrite an existing bond during keys distribution phase when the identity address of the bond is known
BT: Possible to overwrite an existing bond during keys distribution phase when the identity address of the bond is known. Zephyr versions >= 1.14.2, >= 2.4.0, >= 2.5.0 contain Use of Multiple Resources with Duplicate Identifier (CWE-694). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-j76f-35mc-4h63
Attack profile
How easy it is to exploit
- Attack vector
- Adjacent network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
BT: Possible to overwrite an existing bond during keys distribution phase when the identity address of the bond is known
BT: Possible to overwrite an existing bond during keys distribution phase when the identity address of the bond is known. Zephyr versions >= 1.14.2, >= 2.4.0, >= 2.5.0 contain Use of Multiple Resources with Duplicate Identifier (CWE-694). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-j76f-35mc-4h63
- Record
CVE-2021-3436- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Weakness
- CWE-694
- Updated
- 2026-11-02
EUVDEUVD-2021-26762
BT: Possible to overwrite an existing bond during keys distribution phase when the identity address of the bond is known. Zephyr versions >= 1.14.2, >= 2.4.0, >= 2.5.0 contain Use of Multiple Resources with Duplicate Identifier (CWE-694). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-j76f-35mc-4h63
- Record
EUVD-2021-26762- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-03
NVD
BT: Possible to overwrite an existing bond during keys distribution phase when the identity address of the bond is known. Zephyr versions >= 1.14.2, >= 2.4.0, >= 2.5.0 contain Use of Multiple Resources with Duplicate Identifier (CWE-694). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-j76f-35mc-4h63
- Record
CVE-2021-3436- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L - CVSS 2.0
- 6.4 Medium
AV:N/AC:L/Au:N/C:N/I:P/A:P - Weakness
- CWE-694
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-3436 is a medium vulnerability (CVSS 4.3) in Zephyrproject Zephyr, published October 5, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.98%, the 62nd percentile. No source names a fixed version.