CVE-2026-27703

RIOT is an open-source microcontroller operating system, designed to match the requirements of Internet of Things (IoT) devices and other embedded devices. In 2026.01 and earlier, the default handler for the well_known_core resource coap_well_known_core_default_handler writes user-provided option data and other data into a fixed size buffer without validating the buffer is large enough to contain the response. This vulnerability allows an attacker to corrupt neighboring stack location, including security-sensitive addresses like the return address, leading to denial of service or arbitrary code execution.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/RIOT-OS/RIOT/security/advisories/GHSA-qgj4-9jff-93cj	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:o:riot-os:riot:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-11 20:16

Updated : 2026-03-16 20:19

NVD link : CVE-2026-27703

Mitre link : CVE-2026-27703

CVE.ORG link : CVE-2026-27703

JSON object : View

Products Affected

riot-os

riot

CWE

CWE-787

Out-of-bounds Write

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