{"cve":"CVE-2021-32771","nvd":{"published":"2022-08-04T21:15:07.907","modified":"2026-06-17T03:53:35.790","status":"Modified","description":"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_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","score":8.1},"cwes":["CWE-120"],"references":["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"],"products":["contiki-ng:contiki-ng"],"source":"nvd","synced_at":"2026-10-19T21:34:18.502168378+00:00"},"epss":{"cve":"CVE-2021-32771","score":0.01353,"percentile":0.71589,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}