What is CVE-2026-7426?

CVE-2026-7426 is a high-severity vulnerability in Amazon Freertos-plus-tcp, classified under Out-of-bounds Write. CVSS score: 8.1/10. Published 2026-04-29.

How severe is CVE-2026-7426?

High severity. CVSS v3 base score is 8.1 out of 10.

Buffer overflow in Amazon Freertos-plus-tcp

CVE-2026-7426

Insufficient validation of the prefix length field in IPv6 Router Advertisement processing in FreeRTOS-Plus-TCP before V4.2.6 and V4.4.1 allows an adjacent network actor to cause memory corruption by sending a crafted Router Advertisement…

Vulnerability class: Buffer Overflow

EPSS: 0.000 (6.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/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-787 — Out-of-bounds Write

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-2026-7426?: CVE-2026-7426 is a high-severity vulnerability in Amazon Freertos-plus-tcp, classified under Out-of-bounds Write. CVSS score: 8.1/10. Published 2026-04-29.
How severe is CVE-2026-7426?: High severity. CVSS v3 base score is 8.1 out of 10.