CVE-2025-40820EPSS p40.0%

CVE-2025-40820CVE-2025-40820

Description

Affected products do not properly enforce TCP sequence number validation in specific scenarios but accept values within a broad range. This could allow an unauthenticated remote attacker e.g. to interfere with connection setup, potentially leading to a denial of service. The attack succeeds only if an attacker can inject IP packets with spoofed addresses at precisely timed moments, and it affects only TCP-based services.

Scoring

CVSS 7.5 ()
VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS0.49% probability of exploitation · percentile 40.0% · 2026-10-05T12:00:23Z
Last modified2026-09-30
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.