What is CVE-2026-7423?

CVE-2026-7423 is a medium-severity vulnerability in Amazon Freertos-plus-tcp, classified under Integer Underflow. CVSS score: 5.3/10. Published 2026-04-29.

How severe is CVE-2026-7423?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Integer overflow in Amazon Freertos-plus-tcp

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 si…

EPSS: 0.000 (7.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Amazon Freertos-plus-tcp
Aws Freertos-plus-tcp — versions 4.0.0, 4.3.0, 4.2.6

Weakness classification (CWE)

CWE-191 — Integer Underflow

References

ff89ba41-3aa1-4d27-914a-91399e9639e5 (vendor-advisory, Vendor Advisory)
ff89ba41-3aa1-4d27-914a-91399e9639e5 (patch, Release Notes)
ff89ba41-3aa1-4d27-914a-91399e9639e5 (patch, Release Notes)
ff89ba41-3aa1-4d27-914a-91399e9639e5 (Patch, third-party-advisory, Vendor Advisory)

Frequently asked questions

What is CVE-2026-7423?: CVE-2026-7423 is a medium-severity vulnerability in Amazon Freertos-plus-tcp, classified under Integer Underflow. CVSS score: 5.3/10. Published 2026-04-29.
How severe is CVE-2026-7423?: Medium severity. CVSS v3 base score is 5.3 out of 10.