CVE-2022-41873

Out-of-bounds read and write in BLE L2CAP module

Published Nov 11, 2022 CVSS 3.1 · 4.2 Medium EPSS < 1% KEV · Not listed

Description

Contiki-NG is an open-source, cross-platform operating system for Next-Generation IoT devices. Versions prior to 4.9 are vulnerable to an Out-of-bounds read. While processing the L2CAP protocol, the Bluetooth Low Energy stack of Contiki-NG needs to map an incoming channel ID to its metadata structure. While looking up the corresponding channel structure in get_channel_for_cid (in os/net/mac/ble/ble-l2cap.c), a bounds check is performed on the incoming channel ID, which is meant to ensure that the channel ID does not exceed the maximum number of supported channels.However, an integer truncation issue leads to only the lowest byte of the channel ID to be checked, which leads to an incomplete out-of-bounds check. A crafted channel ID leads to out-of-bounds memory to be read and written with attacker-controlled data. The vulnerability has been patched in the "develop" branch of Contiki-NG, and will be included in release 4.9. As a workaround, Users can apply the patch in Contiki-NG pull request 2081 on GitHub.

Analysis

No analysis available yet

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

contiki-ng

affected

Version	Status	Constraints
`< 4.9`	affected	—

Configuration 1 [-]

cpe:2.3:o:contiki-ng:contiki-ng:*:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No remediation available yet

Tracking

Advisories

Source	ID	Title
EUVD	EUVD-2022-45037	Contiki-NG is an open-source, cross-platform operating system for Next-Generation IoT devices. Versions prior to 4.9 are vulnerable to an Out-of-bounds read. While processing the L2CAP protocol, the Bluetooth Low Energy stack of Contiki-NG needs to map an incoming channel ID to its metadata structure. While looking up the corresponding channel structure in get_channel_for_cid (in os/net/mac/ble/ble-l2cap.c), a bounds check is performed on the incoming channel ID, which is meant to ensure that the channel ID does not exceed the maximum number of supported channels.However, an integer truncation issue leads to only the lowest byte of the channel ID to be checked, which leads to an incomplete out-of-bounds check. A crafted channel ID leads to out-of-bounds memory to be read and written with attacker-controlled data. The vulnerability has been patched in the "develop" branch of Contiki-NG, and will be included in release 4.9. As a workaround, Users can apply the patch in Contiki-NG pull request 2081 on GitHub.