CVE-2021-21279 json
Infinite loop in IPv6 neighbor solicitation processing
published 2021-06-18 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-8650
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.0%
- EPSS 1.0% chance of exploitation in 30 days, percentile 62%
- public exploits
- 0
- none known
Summary
Contiki-NG is an open-source, cross-platform operating system for internet of things devices. In verions prior to 4.6, an attacker can perform a denial-of-service attack by triggering an infinite loop in the processing of IPv6 neighbor solicitation (NS) messages. This type of attack can effectively shut down the operation of the system because of the cooperative scheduling used for the main parts of Contiki-NG and its communication stack. The problem has been patched in Contiki-NG 4.6. Users can apply the patch for this vulnerability out-of-band as a workaround.
Patch / fix
- contiki-ng contiki-ng 4.6
Exploit prediction
0.98% chance of exploitation in the next 30 days, higher than 62% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 7.8 | AV:N/AC:L/Au:N/C:N/I:N/A:C |
Affected products
- contiki-ng contiki-ng
Classification
- Weakness
-
- CWE-835 Loop with Unreachable Exit Condition
References
-
github.com
/contiki-ng/contiki-ng/security/advisories/GHSA-rr5j-j8m8-fc4f
third-party-advisory
Sources
- CVE List CVE-2021-21279
- NVD CVE-2021-21279
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