CVE-2017-0143VulnerabilityPublished 11/03/2021Updated 10/24/2026

CVE-2017-0143: Microsoft Windows Server Message Block (SMBv1) Remote Code Execution Vulnerability

Affects Microsoft WindowsSource CISA KEV

Severity

High

No CVSS score published yet

Exploitation: Actively exploited – in CISA KEV since 11/03/2021
KEV deadline: 05/03/2022
Ransomware: Used in ransomware campaigns
EPSS: 93.3% chance of exploitation in 30 days – higher than 99% of CVEs

What to do

CISA required action

Apply updates per vendor instructions.

nvd.nist.gov/vuln/detail/CVE-2017-0143 (opens in a new tab)

Description

CVE-2017-0143 is a high-severity remote code execution vulnerability in Microsoft Windows Server Message Block 1.0 (SMBv1). This vulnerability allows an attacker to execute arbitrary code remotely via SMBv1. It has been exploited in the wild and is known to have been used in ransomware campaigns.

Summary

Microsoft Windows Server Message Block 1.0 (SMBv1) contains an unspecified vulnerability (CVE-2017-0143) that enables remote code execution. This vulnerability has been actively exploited in the wild, including in ransomware attacks. The exact technical details of the vulnerability are not provided in the input data. No specific affected versions or patch information is included in the provided data.

Impact

Successful exploitation of this vulnerability allows remote attackers to execute arbitrary code on affected Windows systems via SMBv1. This can lead to full system compromise, enabling attackers to deploy ransomware or other malicious payloads. The vulnerability has been observed in active exploitation campaigns.

Mitigation

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since this vulnerability involves SMBv1, disabling SMBv1 protocol on Windows systems is a commonly recommended mitigation. However, no explicit vendor advisory or patch information is provided in the input data, so consult Microsoft security advisories for official fixes or mitigations.

Weaknesses

CWE-20Improper Input Validation (opens in a new tab)

What to do

Description

AnalysisAI-generated, updated 10/24/2026, 09:19:12 UTC

Weaknesses

References

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