CVE-2026-102552: Improper verification of the source of a communication channel in FreeRTOS-Plus-TCP DNS resolver
Improper verification of the source of a communication channel in the DNS resolver in Amazon FreeRTOS-Plus-TCP before V4.4.2 might allow remote third-party to insert a chosen address into the device's DNS cache via a forged DNS reply.
To remediate this issue, users should upgrade to version V4.4.2 and enable ipconfigDNSCHECKREPLYSOURCEIP.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Amazon FreeRTOS-Plus-TCPto a version that resolves this vulnerability.Fixed in V4.4.2 - Configuration
Enable ipconfigDNS_CHECK_REPLY_SOURCE_IP.
Amazon FreeRTOS-Plus-TCP DNS resolver ipconfigDNS_CHECK_REPLY_SOURCE_IP = enabled
Event History
Frequently Asked Questions
Which deployments are exposed to this issue?
Devices using the FreeRTOS-Plus-TCP DNS resolver in versions before V4.4.2 are affected if DNS reply source-IP checking is not enabled.
What does an attacker need to exploit it?
A remote third party needs to provide a forged DNS reply that is accepted by the resolver. Successful exploitation can place an attacker-chosen address in the device DNS cache.
Is upgrading alone the stated remediation?
No. The stated remediation is to upgrade to FreeRTOS-Plus-TCP V4.4.2 and enable ipconfigDNS_CHECK_REPLY_SOURCE_IP.