← Back to results
Vulnerability record · public intelligence
CVE-2021-28362
HIGH

CVE-2021-28362

Published Mar 24, 2021 · Updated Oct 23, 2026

Severity · CVSSHIGH · 7.5
Known exploitationNot listed
EPSS / likelihood1.35%
QFinch risk score10 / 100

Original summary

Normalized public record · Updated Oct 23, 2026

An issue was discovered in Contiki through 3.0. When sending an ICMPv6 error message because of invalid extension header options in an incoming IPv6 packet, there is an attempt to remove the RPL extension headers. Because the packet length and the extension header length are unchecked (with respect to the available data) at this stage, and these variables are susceptible to integer underflow, it is possible to construct an invalid extension header that will cause memory corruption issues and lead to a Denial-of-Service condition. This is related to rpl-ext-header.c.

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

An issue was discovered in Contiki through 3.0. When sending an ICMPv6 error message because of invalid extension header options in an incoming IPv6 packet, there is an attempt to remove the RPL extension headers. Because the packet length and the extension header length are unchecked (with respect to the available data) at this stage, and these variables are susceptible to integer underflow, it is possible to construct an invalid extension header that will cause memory corruption issues and lead to a Denial-of-Service condition. This is related to rpl-ext-header.c.

Evidence: public source records

Affected products

Affected scope reported by the available public evidence
Affected package, product or rangeFix status
Consult the referenced vendor advisory for affected versions.Consult source advisory

Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.

Remediation

Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.

  1. Confirm the affected product and reachable code path exist in your environment.
  2. Apply the vendor-supported patch or mitigation from the primary advisory.
  3. Rescan the exact deployed revision and retain verification evidence.
Review primary references

Evidence coverage

CVENVDEPSS
SSVC priority
MEDIUM
Confidence
10%
Aliases
None reported

Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.

Sources and record history

  1. www.kb.cert.org ↗
  2. Source repository ↗

Record history

Published Mar 24, 2021 · Last refreshed Oct 23, 2026