CVE-2026-7423
CWE-191Published: April 29, 2026· Updated: May 4, 2026
Official Description
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.
Technical Analysis
CVE-2026-7423 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 availability disruption (denial of service), with a CVSS base score of 6.5.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (4)
Quick Facts
Related CVEs (CWE-191)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-7423 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts