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TI-2023-16946 Aliases CVE-2023-34100

Out-of-Bounds Read in contiki-ng

Priority LOW 38CWE-125Published · Updated

Key facts

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

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

Summary

Contiki-NG is an open-source, cross-platform operating system for IoT devices. When reading the TCP MSS option value from an incoming packet, the Contiki-NG OS does not verify that certain buffer indices to read from are within the bounds of the IPv6 packet buffer, uip_buf. In particular, there is a 2-byte buffer read in the module os/net/ipv6/uip6.c. The buffer is indexed using 'UIP_IPTCPH_LEN + 2 + c' and 'UIP_IPTCPH_LEN + 3 + c', but the uip_buf buffer may not have enough data, resulting in a 2-byte read out of bounds. The problem has been patched in the "develop" branch of Contiki-NG, and is expected to be included in release 4.9. Users are advised to watch for the 4.9 release and to upgrade when it becomes available. There are no workarounds for this vulnerability aside from manually patching with the diff in commit `cde4e9839`.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00437 38th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
contiki-ngcontiki-ngup to 4.8—No fix listedCNA
  • contiki-ng Vendorcontiki-ng Affected up to 4.8 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:contiki-ng:contiki-ng:*:*:*:*:*:*:*:*up to 4.8Vulnerablecontiki-ng
  • cpe:2.3:o:contiki-ng:contiki-ng:*:*:*:*:*:*:*:* Versions up to 4.8 Vulnerable ·contiki-ng

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-34100

References

Patch 1

Advisory 1

  • 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