CVE-2021-21281
Estado: ModificadaCrítica (9.8)—
Contiki-NG is an open-source, cross-platform operating system for internet of things devices. A buffer overflow vulnerability exists in Contiki-NG versions prior to 4.6. After establishing a TCP socket using the tcp-socket library, it is possible for the remote end to send a packet with a data offset that is unvalidated. The problem has been patched in Contiki-NG 4.6. 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:H/A:H
- Puntuación base: 9.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.92%
- Percentil entre todas las CVEs puntuadas: 59
- 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-120
Referencias
JSON original (NVD)
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"value": "Contiki-NG is an open-source, cross-platform operating system for internet of things devices. A buffer overflow vulnerability exists in Contiki-NG versions prior to 4.6. After establishing a TCP socket using the tcp-socket library, it is possible for the remote end to send a packet with a data offset that is unvalidated. The problem has been patched in Contiki-NG 4.6. 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 del Internet de las cosas. Se presenta una vulnerabilidad de desbordamiento de búfer en las versiones de Contiki-NG anteriores a 4.6. Después de haber establecido un socket TCP usando la biblioteca tcp-socket, es posible para el extremo remoto enviar un paquete con un desplazamiento de datos que no está validado. El problema ha sido parcheado en Contiki-NG versión 4.6. Los usuarios pueden aplicar el parche para esta vulnerabilidad fuera de límite como solución alternativa"
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"lastModified": "2026-06-17T03:35:11.187",
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