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Vulnerability record · CVE-2021-21282 · published 18 June 2021

CVE-2021-21282: Contiki-ng classic buffer overflow vulnerability

Contiki Ng · Contiki Ng

Contiki-NG is an open-source, cross-platform operating system for internet of things devices. In versions prior to 4.5, buffer overflow can be triggered by an input packet when using either of Contiki-NG's two RPL implementations in source-routing mode. The problem has been patched in Contiki-NG 4.5. Users can apply the patch for this vulnerability out-of-band as a workaround.

9.8 CVSS 3.1 Critical EPSS 0.99% · top 38.9% CWE-120 · Classic buffer overflow
9.8CVSS 3.1 base score, v2 7.5
0.99%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
4References
17 Jun 2026Last modified by NVD

Description

Contiki-NG is an open-source, cross-platform operating system for internet of things devices. In versions prior to 4.5, buffer overflow can be triggered by an input packet when using either of Contiki-NG's two RPL implementations in source-routing mode. The problem has been patched in Contiki-NG 4.5. Users can apply the patch for this vulnerability out-of-band as a workaround.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/contiki-ng/contiki-ng/pull/1183 PatchThird Party Advisory
https://github.com/contiki-ng/contiki-ng/security/advisories/GHSA-6xf2-77gf-fgjx PatchThird Party Advisory
https://github.com/contiki-ng/contiki-ng/pull/1183 PatchThird Party Advisory
https://github.com/contiki-ng/contiki-ng/security/advisories/GHSA-6xf2-77gf-fgjx PatchThird Party Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-21282), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.