CVE-2021-28136

Description

The Bluetooth Classic implementation in Espressif ESP-IDF 4.4 and earlier does not properly handle the reception of multiple LMP IO Capability Request packets during the pairing process, allowing attackers in radio range to trigger memory corruption (and consequently a crash) in ESP32 via a replayed (duplicated) LMP packet.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.29%
Vendor Advisory espressif.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/espressif/esp-idf product third party advisory
https://github.com/espressif/esp32-bt-lib product third party advisory
https://www.espressif.com/en/products/socs/esp32 product vendor advisory
https://dl.packetstormsecurity.net/papers/general/braktooth.pdf third party advisory technical description

Frequently Asked Questions

What is the severity of CVE-2021-28136?
CVE-2021-28136 has been scored as a medium severity vulnerability.
How to fix CVE-2021-28136?
To fix CVE-2021-28136, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-28136 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-28136 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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