CVE-2026-7423

Integer underflow in the ICMP and ICMPv6 echo reply handlers in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network user to cause a denial of service (device crash) when outgoing ping support is enabled, because header sizes are subtracted from a packet length field without validating the field is large enough, resulting in a heap out-of-bounds read of up to approximately 65KB. To mitigate this issue, users should upgrade to the fixed version when available.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 3.6

Attack Vector ADJACENT_NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://aws.amazon.com/security/security-bulletins/2026-021-aws/	Vendor Advisory
https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.2.6	Release Notes
https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.4.1	Release Notes
https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/security/advisories/GHSA-7r59-2pgv-9v2r	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:amazon:freertos-plus-tcp::::::::
	cpe:2.3:a:amazon:freertos-plus-tcp::::::::

History

No history.

Information

Published : 2026-04-29 19:16

Updated : 2026-06-17 11:02

NVD link : CVE-2026-7423

Mitre link : CVE-2026-7423

CVE.ORG link : CVE-2026-7423

JSON object : View

Products Affected

amazon

freertos-plus-tcp

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

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