CVE-2021-21410

critical

Description

Contiki-NG is an open-source, cross-platform operating system for Next-Generation IoT devices. An out-of-bounds read can be triggered by 6LoWPAN packets sent to devices running Contiki-NG 4.6 and prior. The IPv6 header decompression function (<code>uncompress_hdr_iphc</code>) does not perform proper boundary checks when reading from the packet buffer. Hence, it is possible to construct a compressed 6LoWPAN packet that will read more bytes than what is available from the packet buffer. As of time of publication, there is not a release with a patch available. Users can apply the patch for this vulnerability out-of-band as a workaround.

References

Details

Source: Mitre, NVD

Published: 2021-06-18

Updated: 2026-06-17

Risk Information

CVSS v2

Base Score: 6.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:P

Severity: Medium

CVSS v3

Base Score: 9.1

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Severity: Critical

EPSS

EPSS: 0.00433