Is CVE-2026-7426 actively exploited?

No active exploitation of CVE-2026-7426 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-7426 be exploited remotely?

Partially. CVE-2026-7426 requires adjacent network access (same network segment) to exploit.

What is the CVSS score of CVE-2026-7426?

CVE-2026-7426 has a CVSS score of 8.1 (HIGH).

HOME VULNERABILITIESCVE-2026-7426

HIGH

CVE-2026-7426

CWE-787Published: April 29, 2026· Updated: May 4, 2026

8.1

CVSS v3.1

EPSS:0.01%probability of exploitation in 30 daysPercentile:3.4th

Official Description

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 with a prefix length value exceeding the maximum valid length, resulting in a heap buffer overflow. Users processing IPv4 RA only are not impacted.

To mitigate this issue, users should upgrade to the fixed version when available.

NVD Source

Technical Analysis

CVE-2026-7426 requires adjacent network access, limiting remote exploitation but still posing risk in shared or local network environments.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 8.1.

From a weakness classification perspective (CWE-787): Out-of-bounds write vulnerabilities can lead to data corruption, crashes, or arbitrary code execution.