CVE-2021-3436 Race condition in zephyr
An attacker can overwrite an existing Bluetooth bond during key distribution if the identity address is known, bypassing authentication in Zephyr RTOS.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-3436?
CVE-2021-3436 is a medium-severity vulnerability in Zephyrproject Zephyr, published on 5 Oct 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Official 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
Weakness: CWE-694
Which versions are affected by CVE-2021-3436?
It affects 1 product.
Products include Zephyrproject Zephyr.
How do I fix CVE-2021-3436?
No fix has been published for CVE-2021-3436 yet. Limit exposure of the affected software until one is available.
Is CVE-2021-3436 being exploited?
There is no known exploitation of CVE-2021-3436 in the wild and no public exploit code.
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- CVE-2018-1000800 Null dereference in n/a
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