VULNERABILITY INTELLIGENCE
CVE-2025-40820
CVSS score7.5 HIGH
EPSS probability0.49%
CISA KEVNot currently listed
Published2025-12-09
Last modified2026-10-07
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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.
Weakness classification
- productcert@siemens.com: CWE-940