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TI-2026-75375 Aliases CVE-2026-49868

Out-of-bounds read in RIOT DHCPv6 client via missing length check

Priority MEDIUM 43CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-191 and the CVSS impact.

Summary

RIOT, an open-source operating system for IoT and embedded devices, is affected before 2026.07 in its DHCPv6 client. The client does not check minimum option lengths before parsing IA_PD and IA_NA options, which causes an integer underflow and unbounded out-of-bounds heap reads (CWE-125). A malicious or compromised DHCPv6 server can trigger this, which can crash the device and may expose or corrupt memory.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

RIOT is an open-source microcontroller operating system designed for Internet of Things devices and other embedded systems. Prior to 2026.07, _parse_reply() in sys/net/application_layer/dhcpv6/client.c omits minimum-length validation before passing IA_PD and IA_NA option bodies to sub-option parsers. A malicious or compromised DHCPv6 server can send a REPLY with an option length smaller than the required structure while MODULE_DHCPV6_CLIENT_IA_PD is enabled, causing _parse_ia_pd_option to read past the option body, size_t underflow, and unbounded out-of-bounds heap reads that can crash the device and may expose or corrupt memory. This issue is fixed in version 2026.07.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00371 31st percentileScored 2026-11-07
Fix Fixed RIOT (RIOT-OS): 2026.07

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

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

Affected products

VendorProductAffected versionsFixed inStatusSource
RIOT-OSRIOTbefore 2026.072026.07Patch availableCNA
  • RIOT VendorRIOT-OS Affected before 2026.07 Fixed in 2026.07 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:riot-os:riot:*:*:*:*:*:*:*:*——RIOT-OS
  • cpe:2.3:o:riot-os:riot:*:*:*:*:*:*:*:* Versions — — ·RIOT-OS

Remediation

Update RIOT to version 2026.07, which fixes this issue.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA RIOT (RIOT-OS) Fixed in 2026.07

Timeline

  1. 2026-10-16 Threatist record created from CVE-2026-49868
  2. 2026-10-21 CISA SSVC decision points changed

References

Other 4

  • TI-2024-21112 Buffer overflows in RIOT CVSS 3.1CRITICAL 9.8
  • TI-2023-16843 RIOT-OS vulnerable to Out of Bounds Write in _rbuf_add CVSS 3.1CRITICAL 9.8
  • TI-2023-10319 RIOT-OS vulnerable to Buffer Overflow during IPHC receive CVSS 3.1CRITICAL 9.8
  • TI-2026-22079 RIOT has an Out-of-Bounds Write in nanoCoAP Handler CVSS 3.1CRITICAL 9.8
  • TI-2023-16842 RIOT-OS vulnerable to Race Condition in SFR Timeout CVSS 3.1HIGH 7.5
  • TI-2023-16841 RIOT-OS vulnerable to NULL pointer dereference during NHC encoding CVSS 3.1HIGH 7.5
See all 45 →

Sources

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