CVE-2021-32771
Buffer overflow in contiki-ng
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
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.
Timeline
ID reserved
By GitHub_M
- 15 months later
· 15 months later
Published
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | High8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 1.4% · top 28% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.1.
Weakness
Affected products
- affected < 4.8
References (4)
- https://github.com/contiki-ng/contiki-ng/security/advisories/GHSA-jqjf-v7v9-xp6w (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/contiki-ng/contiki-ng/pull/1615 (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/contiki-ng/contiki-ng/pull/1615/commits/587ae59956e00316fd44fd7072ac3a6a07b4b20f (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/contiki-ng/contiki-ng/releases/tag/release%2Fv4.8 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-32771)Record last updated .