CVE-2021-21282: Buffer overflow in RPL source routing header processing

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-06-18 · updated 2026-06-17
Weakness: CWE-120

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.

Affected products

contiki-ng: before 4.5 — fixed in 4.5

How to fix

Upgrade to a fixed version: contiki-ng 4.5. Check the vendor advisory for mitigations.

References

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

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