CVE-2021-21280: Out-of-bounds write when processing 6LoWPAN extension headers

Published Jun 18, 2021
·
Updated

Contiki-NG is an open-source, cross-platform operating system for internet of things devices. It is possible to cause an out-of-bounds write in versions of Contiki-NG prior to 4.6 when transmitting a 6LoWPAN packet with a chain of extension headers. Unfortunately, the written header is not checked to be within the available space, thereby making it possible to write outside the buffer. The problem has been patched in Contiki-NG 4.6. Users can apply the patch for this vulnerability out-of-band as a workaround.

Affected Software

1 affected component
Contiki-NG Contiki-NG<4.6

Event History

Jun 18, 2021
CVE Published
via MITRE·08:35 PM
Data Sourced
via MITRE·08:35 PM
DescriptionSeverityWeakness

Frequently Asked Questions

1

What is CVE-2021-21280?

CVE-2021-21280 is a vulnerability in Contiki-NG, an open-source operating system for internet of things devices, that allows for an out-of-bounds write when transmitting a 6LoWPAN packet with a chain of extension headers.

2

How severe is CVE-2021-21280?

CVE-2021-21280 has a severity rating of 9.8 out of 10, indicating a critical vulnerability.

3

How can CVE-2021-21280 be exploited?

CVE-2021-21280 can be exploited by sending a 6LoWPAN packet with a chain of extension headers, which triggers an out-of-bounds write and potential arbitrary code execution.

4

Is there a fix available for CVE-2021-21280?

Yes, a fix for CVE-2021-21280 is included in Contiki-NG version 4.6 and later.

5

Where can I find more information about CVE-2021-21280?

You can find more information about CVE-2021-21280 in the GitHub pull request: https://github.com/contiki-ng/contiki-ng/pull/1409 and the security advisory: https://github.com/contiki-ng/contiki-ng/security/advisories/GHSA-r768-hrhf-v592

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