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…
CVE-2026-7423 · Severity: medium · CVSS 5.3 · Published 2026-04-29
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.
No. Junglewise Threat Intelligence has no report of CVE-2026-7423 being exploited in the wild.
How severe is CVE-2026-7423?
Medium severity, with a CVSS score of 5.3, published 29 April 2026.
Which products and versions are affected?
Amazon Freertos-Plus-Tcp. The advisory does not name versions.
Is there a fix for CVE-2026-7423?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
Am I affected by CVE-2026-7423?
Check whether you run Amazon Freertos-Plus-Tcp. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.