CVE-2026-7423CWE-191

Integer Underflow in ICMP Echo Reply Processing in FreeRTOS-Plus-TCP

Medium · published April 29, 2026

CVSS v4.0
6.0
EPSS
0%
Percentile
28.4
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
6.0 · MEDIUM
Vector
CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
EPSS
0.00358 · 28.4th percentile
Weakness
CWE-191 · Integer Underflow (Wrap or Wraparound)
Published
2026-04-29T18:36Z
EPSS history
Timeline
  • 29 APR 18:36Z
    Integer Underflow in ICMP Echo Reply Processing in FreeRTOS-Plus-TCP
    cvelistv5