CVE-2021-32771
Contiki-NG is an open-source, cross-platform operating system for IoT devices. In affected versions it is possible to cause a buffer overflow when copying an IPv6 address prefix in the RPL-Classic implementation in Contiki-NG. In order to trigger the vulnerability, the Contiki-NG system must have joined an RPL DODAG. After that, an attacker can send a DAO packet with a Target option that contains a prefix length larger than 128 bits. The problem was fixed after the release of Contiki-NG 4.7. Users unable to upgrade may apply the patch in Contiki-NG PR #1615.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 8.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.31%
- Percentil entre todas las CVEs puntuadas: 70
- 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
- https://github.com/contiki-ng/contiki-ng/pull/1615
- https://github.com/contiki-ng/contiki-ng/pull/1615/commits/587ae59956e00316fd44fd7072ac3a6a07b4b20f
- https://github.com/contiki-ng/contiki-ng/releases/tag/release%2Fv4.8
- https://github.com/contiki-ng/contiki-ng/security/advisories/GHSA-jqjf-v7v9-xp6w
- https://github.com/contiki-ng/contiki-ng/pull/1615
- https://github.com/contiki-ng/contiki-ng/pull/1615/commits/587ae59956e00316fd44fd7072ac3a6a07b4b20f
- https://github.com/contiki-ng/contiki-ng/releases/tag/release%2Fv4.8
- https://github.com/contiki-ng/contiki-ng/security/advisories/GHSA-jqjf-v7v9-xp6w
JSON original (NVD)
Mostrar
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