CVE-2021-21410
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.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
- Puntuación base: 9.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.23%
- Percentil entre todas las CVEs puntuadas: 68
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- CWE-125
Referencias
JSON original (NVD)
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"value": "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."
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"value": "Contiki-NG es un sistema operativo de código abierto y multiplataforma para dispositivos IoT de próxima generación. Una lectura fuera de límites puede ser desencadenada por los paquetes 6LoWPAN enviados a dispositivos que ejecutan Contiki-NG versiones 4.6 y anteriores. La función de descompresión de encabezados IPv6 ((code)uncompress_hdr_iphc(/code)) no lleva a cabo comprobaciones de límites apropiadas al leer del búfer del paquete. Por lo tanto, es posible construir un paquete 6LoWPAN comprimido que leerá más bytes de los que están disponibles en el búfer del paquete. En el momento de la publicación, no se presenta una versión con un parche disponible. Los usuarios pueden aplicar el parche para esta vulnerabilidad fuera de límite como solución alternativa"
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"lastModified": "2026-06-17T03:35:31.237",
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