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TI-2021-04508 Aliases CVE-2021-21410

Out-of-bounds read in the 6LoWPAN implementation

Priority MEDIUM 42CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

Contiki-NG is an open-source, cross-platform operating system for Next-Generation IoT devices. An out-of-bounds read can be triggered by 6LoWPAN packets sent to devices running Contiki-NG 4.6 and prior. The IPv6 header decompression function (<code>uncompress_hdr_iphc</code>) does not perform proper boundary checks when reading from the packet buffer. Hence, it is possible to construct a compressed 6LoWPAN packet that will read more bytes than what is available from the packet buffer. As of time of publication, there is not a release with a patch available. Users can apply the patch for this vulnerability out-of-band as a workaround.

Why it matters now

EPSS 0.0123 69th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
contiki-ngcontiki-ngup to 4.6—No fix listedCNA
  • contiki-ng Vendorcontiki-ng Affected up to 4.6 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:contiki-ng:contiki-ng:*:*:*:*:*:*:*:*up to 4.6Vulnerablecontiki-ng
  • cpe:2.3:o:contiki-ng:contiki-ng:*:*:*:*:*:*:*:* Versions up to 4.6 Vulnerable ·contiki-ng

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-21410

References

Patch 2

  • TI-2020-14885 An issue was discovered in Contiki through 3.0 and Contiki-NG through 4.5. CVSS 3.1CRITICAL 9.8
  • TI-2020-16751 In Contiki 4.5, TCP ISNs are improperly random. CVSS 3.1CRITICAL 9.1
  • TI-2018-16029 contiki-ng version 4 contains a Buffer Overflow vulnerability in AQL (Antelope Query… CVSS 3.1CRITICAL 9.8
  • TI-2018-13749 An issue was discovered in the MQTT server in Contiki-NG before 4.2. CVSS 3.0CRITICAL 10.0
  • TI-2023-14381 Contiki-NG has off-by-one error in Antelope DBMS CVSS 3.1CRITICAL 9.8
  • TI-2023-14839 Contiki-NG missing NULL pointer check in IPv6 neighbor discovery CVSS 3.1CRITICAL 9.8
See all 41 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences