CVE intelligence and bounded remediation

CVE-2021-21279 — Contiki-NG is an open-source, cross-platform operating system for internet of things devices

High CVSS 7.8

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.

Severity
High
CVSS
7.8 (2.0)
Published
2021-06-18
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-835

Affected products

  • contiki-ng / contiki-ng

Matched remediation archetype

Resource exhaustion and denial of service

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify attacker-influenced work factors including input size, nesting, compression, fan-out, regex cost, allocation, recursion, retries, and connection lifetime.
  • Map per-request and shared CPU, memory, disk, descriptor, thread, queue, and downstream-service limits.
  • Determine whether authentication, tenancy, quotas, and rate controls apply before expensive processing begins.

Remediate safely

  • Bound input size, nesting, expansion, work, concurrency, queue depth, retries, and execution time before resource-intensive processing.
  • Release resources on every success, error, cancellation, and timeout path and use backpressure instead of unbounded buffering.
  • Update affected components and add small deterministic tests that assert resource ceilings rather than exhausting a host.

Authoritative sources

Complete CVE record and remediation plan

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