CVE-2020-1118: Microsoft Windows Transport Layer Security Denial of Service Vulnerability

Published May 12, 2020
·
Updated

A denial of service vulnerability exists in the Windows implementation of Transport Layer Security (TLS) when it improperly handles certain key exchanges, aka 'Microsoft Windows Transport Layer Security Denial of Service Vulnerability'.

Other sources

A denial of service vulnerability exists in the Windows implementation of Transport Layer Security (TLS) when it improperly handles certain key exchanges. An attacker who successfully exploited the vulnerability could cause a target system to stop responding. To exploit this vulnerability, a remote unauthenticated attacker could send a specially crafted request to a target system utilizing TLS 1.2 or lower, triggering the system to automatically reboot. The update addresses the vulnerability by changing the way TLS key exchange messages are validated.

Microsoft

Affected Software

28 affected componentsFixes available
Microsoft Windows 10=1709
Microsoft Windows 10=1803
Microsoft Windows 10=1809
Microsoft Windows 10=1903
Microsoft Windows 10=1909
Microsoft Windows Server 2019
Microsoft Windows Server 2019=1903
Microsoft Windows Server 2019=1909
Microsoft Windows 10=1709
Microsoft Windows 10=1903
Microsoft Windows 10=1903
Microsoft Windows 10=1909
Microsoft Windows 10=1709
Microsoft Windows 10=1709
Microsoft Windows Server=1909
Microsoft Windows 10=1903
Microsoft Windows Server=1903
Microsoft Windows 10=1909
Microsoft Windows 10=1909
Microsoft Windows Server 2019
Microsoft Windows 10=1809
Microsoft Windows 10=1803
Microsoft Windows 10=1809
Microsoft Windows 10=1809
Microsoft Windows Server 2019
Microsoft Windows 10=1803
Microsoft Windows 10=1803
Microsoft Windows Server=1803

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Patch KB4556812
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Patch KB4556799
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Patch KB4551853
  4. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Patch KB4556807

Event History

May 12, 2020
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·02:00 PM
Affected Software
Updated
via Microsoft·02:00 PM
DescriptionSeverity
May 21, 2020
CVE Published
via MITRE·10:53 PM
Data Sourced
via MITRE·10:53 PM
DescriptionSeverity
Data Sourced
via NVD·11:15 PM
RemedyDescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2020-1118?

CVE-2020-1118 has been rated as critical due to its potential to cause a denial of service.

2

How do I fix CVE-2020-1118?

To fix CVE-2020-1118, apply the latest security updates provided by Microsoft for the affected Windows versions.

3

What is the impact of CVE-2020-1118 on Windows systems?

The impact of CVE-2020-1118 is that it can lead to a denial of service, making the system unresponsive.

4

Which versions of Windows are affected by CVE-2020-1118?

CVE-2020-1118 affects specific versions of Windows 10 and Windows Server 2019, including 1709, 1803, 1809, 1903, and 1909.

5

Is there any workaround for CVE-2020-1118?

Microsoft advises users to implement security updates as the primary method to mitigate CVE-2020-1118, and no specific workarounds are provided.

Contact

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