Medium severity · published Oct 5, 2021
CVE-2021-3436
BT: Possible to overwrite an existing bond during keys distribution phase when the identity address of the bond is known
6.5
CVSS
1%
EPSS
No
On KEV
Description
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
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.0% · higher than 62% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ZE
zephyr · zephyrproject-rtos
1.14.2 before unspecified; 2.4.0 before unspecified; 2.5.0 before unspecified · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3436
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3436
Exploit
http://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-j76f-35mc-4h63
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