CVE-2026-7424 PUBLISHED

Integer Underflow in DHCPv6 Sub-Option Parser in FreeRTOS-Plus-TCP

Assigner: AMZN
Reserved: 29.04.2026 Published: 29.04.2026 Updated: 29.04.2026

Integer underflow in the DHCPv6 sub-option parser in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network actor to corrupt the device's IPv6 address assignment, DNS configuration, and lease times, and to cause a denial of service (permanent IP task freeze requiring hardware reset) by sending a single crafted DHCPv6 packet.

The issue is present whenever DHCPv6 is enabled.

To mitigate this issue, users should upgrade to version V4.2.6 or V4.4.1 or newer.

CVSS Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
CVSS Score: 8.1

Attack Vector	Adjacent Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	None
Privileges Required	None	Integrity Impact	High
User Interaction	None	Availability Impact	High

CVSS 3.1

CVSS Vector: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N
CVSS Score: 7.2

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Adjacent	Confidentiality	None	Confidentiality	None
Attack Complexity	Low	Integrity	High	Integrity	None
Attack Requirements	None	Availability	High	Availability	None
Privileges Required	None
User Interaction	None

CVSS 4.0

Product Status

Vendor	AWS
Product	FreeRTOS-Plus-TCP
Versions	Default: unaffected affected from 4.0.0 to 4.2.6 (excl.) affected from 4.3.0 to 4.4.1 (excl.) Version 4.2.6 is unaffected Version 4.4.1 is unaffected

CVE-2026-7424 PUBLISHED

Integer Underflow in DHCPv6 Sub-Option Parser in FreeRTOS-Plus-TCP

Metrics

Product Status

References

Problem Types

Impacts