RIOT OS has buffer overflow in gnrc_ipv6_ext_frag_reass_CVE-2025-66647

1.7 / 10

LOW

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U

Description

RIOT is an open-source microcontroller operating system, designed to match the requirements of Internet of Things (IoT) devices and other embedded devices. A vulnerability was discovered in the IPv6 fragmentation reassembly implementation of RIOT OS v2025.07. When copying the contents of the first fragment (offset=0) into the reassembly buffer, no size check is performed. It is possible to force the creation of a small reassembly buffer by first sending a shorter fragment (also with offset=0). Overflowing the reassembly buffer corrupts the state of other packet buffers which an attacker might be able to used to achieve further memory corruption (potentially resulting in remote code execution). To trigger the vulnerability, the `gnrc_ipv6_ext_frag` module must be included and the attacker must be able to send arbitrary IPv6 packets to the victim. Version 2025.10 fixes the issue.

Basic Information

ID CVE-2025-66647

Source GitHub_M

Published Dec 17, 2025 at 20:21

Modified Dec 17, 2025 at 20:39

Affected Product

Vendor RIOT-OS

Product RIOT

Version < 2025.10

Affected Versions RIOT-OS RIOT < 2025.10

CWE Classification

CWE-120

References

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    "published": "2025-12-17T20:21:13.264Z",
    "modified": "2025-12-17T20:39:34.238Z",
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