Microsoft Windows
CVE-2020-16899 — Windows TCP/IP Denial of Service Vulnerability
Executive Summary
A denial of service vulnerability exists when the Windows TCP/IP stack improperly handles ICMPv6 Router Advertisement packets. An attacker who successfully exploited this vulnerability could cause a target system to stop responding. To exploit this vulnerability, an attacker would have to send specially crafted ICMPv6 Router Advertisement packets to a remote Windows computer. The vulnerability would not allow an attacker to execute code or to elevate user rights directly. The update addresses the vulnerability by correcting how the Windows TCP/IP stack handles ICMPv6 Router Advertisement packets.
Overview
7.5
CVSS HIGH
Important
MS Severity
Not Exploited
MS Exploit Status
More Likely
MS Exploit Likelihood
CVSS Vector
ATTACK VECTOR
Network
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
None
USER INTERACTION
None
SCOPE
Unchanged
Temporal Score: 6.7
EPSS Score
0.13348
probability of exploitation in the next 30 days
0.95919 percentile - updated 2026-06-20
View on FIRST.org
Affected Products
23 affected products
| Product | KB Article | Severity | Impact | Restart Required |
|---|---|---|---|---|
| Windows 10 Version 1709 for 32-bit Systems | 4580328 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 1709 for ARM64-based Systems | 4580328 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 1709 for x64-based Systems | 4580328 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 1803 for 32-bit Systems | 4580330 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 1803 for ARM64-based Systems | 4580330 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 1803 for x64-based Systems | 4580330 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 1809 for 32-bit Systems | 4577668 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 1809 for ARM64-based Systems | 4577668 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 1809 for x64-based Systems | 4577668 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 1903 for 32-bit Systems | 4577671 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 1903 for ARM64-based Systems | 4577671 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 1903 for x64-based Systems | 4577671 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 1909 for 32-bit Systems | 4577671 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 1909 for ARM64-based Systems | 4577671 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 1909 for x64-based Systems | 4577671 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 2004 for 32-bit Systems | 4579311 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 2004 for ARM64-based Systems | 4579311 (Security Update) |
Important | Denial of Service | Yes |
| Windows 10 Version 2004 for x64-based Systems | 4579311 (Security Update) |
Important | Denial of Service | Yes |
| Windows Server 2019 | 4577668 (Security Update) |
Important | Denial of Service | Yes |
| Windows Server 2019 (Server Core installation) | 4577668 (Security Update) |
Important | Denial of Service | Yes |
| Windows Server, version 1903 (Server Core installation) | 4577671 (Security Update) |
Important | Denial of Service | Yes |
| Windows Server, version 1909 (Server Core installation) | 4577671 (Security Update) |
Important | Denial of Service | Yes |
| Windows Server, version 2004 (Server Core installation) | 4579311 (Security Update) |
Important | Denial of Service | Yes |
Patches
5 patches
| Article | Type | Restart |
|---|---|---|
4580328 |
Security Update | Yes |
4580330 |
Security Update | Yes |
4577668 |
Security Update | Yes |
4577671 |
Security Update | Yes |
4579311 |
Security Update | Yes |
Known Exploits
No known exploits have been linked for this CVE yet. When available, exploit references will be sourced from public repositories and may be unverified, incomplete, or non-functional. Always review code carefully before use in any environment.
Acknowledgments
Microsoft Platform Security Assurance & Vulnerability Research
References
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