CVE-2025-40820

HIGH EPSS 33.4%
Published Dec 9, 20256mo ago · Modified Jun 17, 20261w ago
8.7 CVSS 4.0
High
Find Similar
Published Dec 9, 2025 6mo ago
Last Modified Jun 17, 2026 1w ago

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.

CVSS Details

Base Score
8.7
Exploitability
Impact
Vector string
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
33.4% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 1

CWE-940

References 1

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.