Device freeze via post-disconnect ATT callback
Published Oct 19, 2021 · Updated Sep 16, 2024
Use-after-free in Zephyr RTOS 2.4.0 through 2.5.0 allows physically proximate attackers to freeze devices via malformed Bluetooth EATT traffic. The Bluetooth host calls l2cap_chan_sdu_sent() and then bt_att_sent() after disconnect callbacks have freed the ATT channel and context. Exploitation requires an Enhanced ATT L2CAP connection, an invalid ATT request, and immediate disconnection; the reported consequence is a device freeze.
Summary
What happened
Use-after-free in Zephyr RTOS 2.4.0 through 2.5.0 allows physically proximate attackers to freeze devices via malformed Bluetooth EATT traffic. The Bluetooth host calls l2cap_chan_sdu_sent() and then bt_att_sent() after disconnect callbacks have freed the ATT channel and context. Exploitation requires an Enhanced ATT L2CAP connection, an invalid ATT request, and immediate disconnection; the reported consequence is a device freeze.
The record
- CVE
- CVE-2021-3455
- Published
- Oct 19, 2021
- Updated
- Sep 16, 2024
- Vendor
- Zephyr Project
- Product
- Zephyr RTOS
- Classifications
- CWE-416, T1499.004
- Attack vector
- adjacent
- Privileges
- unauthenticated
Timeline
How it unfolded
- Oct 19, 2021CVE publishedPublication date reported by the CVE source.
- Sep 16, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=2.4.0 <unspecified
- Affected versionversion=2.5.0 <unspecified
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
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Your stack
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