Microsoft Windows 10 1903/10 1909/Server 1903/Server 1909 SMBv3 Server Message Block SMBGhost memory corruption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.9$0-$5k0.00

Summaryinfo

A vulnerability labeled as very critical has been found in Microsoft Windows 10 1903/10 1909/Server 1903/Server 1909. Affected is an unknown function of the component SMBv3. The manipulation as part of Server Message Block results in input validation. This vulnerability is reported as CVE-2020-0796. The attack can be launched remotely. Moreover, an exploit is present. A worm is spreading, automatically exploiting this vulnerability. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability, which was classified as very critical, was found in Microsoft Windows 10 1903/10 1909/Server 1903/Server 1909 (Operating System). Affected is an unknown part of the component SMBv3. The manipulation as part of a Server Message Block leads to a input validation vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

A remote code execution vulnerability exists in the way that the Microsoft Server Message Block 3.1.1 (SMBv3) protocol handles certain requests, aka 'Windows SMBv3 Client/Server Remote Code Execution Vulnerability'.

The weakness was disclosed 03/12/2020 as confirmed security update guide (Website). The advisory is shared for download at portal.msrc.microsoft.com. The public release has been coordinated in cooperation with the vendor. This vulnerability is traded as CVE-2020-0796 since 11/04/2019. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details are unknown but a public exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 03/21/2025).

A public exploit has been developed by Daniel García Gutiérrez/Manuel Blanco Parajón in C++ and been published 3 weeks after the advisory. The exploit is shared for download at github.com. It is declared as attacked. As 0-day the estimated underground price was around $100k and more. A worm is spreading, which is automatically exploiting this vulnerability. The advisory illustrates:

To exploit the vulnerability against a server, an unauthenticated attacker could send a specially crafted packet to a targeted SMBv3 server. To exploit the vulnerability against a client, an unauthenticated attacker would need to configure a malicious SMBv3 server and convince a user to connect to it.
This issue was added on 02/10/2022 to the CISA Known Exploited Vulnerabilities Catalog with a due date of 08/10/2022:
Apply updates per vendor instructions.

Applying a patch is able to eliminate this problem. It is possible to mitigate the problem by applying the configuration setting Set-ItemProperty -Path "HKLM:\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters" DisableCompression -Type DWORD -Value 1 -Force.It is possible to mitigate the weakness by firewalling tcp/445. The best possible mitigation is suggested to be patching the affected component. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Exploit-DB (48216). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 10.0
VulDB Meta Temp Score: 9.9

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 10.0
Vendor Vector (Microsoft): 🔍

NVD Base Score: 10.0
NVD Vector: 🔍

CNA Base Score: 10.0
CNA Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Attacked
Author: Daniel García Gutiérrez/Manuel Blanco Parajón
Wormified: 🔍
Programming Language: 🔍
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

KEV Added: 🔍
KEV Due: 🔍
KEV Remediation: 🔍
KEV Ransomware: 🔍
KEV Notice: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Exploit-DB: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍
Exploit Delay Time: 🔍

Config: Set-ItemProperty -Path "HKLM:\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters" DisableCompression -Type DWORD -Value 1 -Force
Firewalling: 🔍

Timelineinfo

11/04/2019 🔍
03/12/2020 +129 days 🔍
03/12/2020 +0 days 🔍
03/13/2020 +1 days 🔍
03/30/2020 +17 days 🔍
03/21/2025 +1817 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: 156731
Status: Confirmed
Coordinated: 🔍

CVE: CVE-2020-0796 (🔍)
GCVE (CVE): GCVE-0-2020-0796
GCVE (VulDB): GCVE-100-151392
scip Labs: https://www.scip.ch/en/?labs.20161215

Entryinfo

Created: 03/13/2020 13:09
Updated: 03/21/2025 21:27
Changes: 03/13/2020 13:09 (58), 03/13/2020 15:27 (19), 04/05/2020 12:05 (4), 10/29/2020 09:42 (5), 04/13/2024 13:10 (18), 04/22/2024 20:30 (9), 09/09/2024 22:29 (1), 02/05/2025 05:15 (12), 03/21/2025 21:27 (1)
Complete: 🔍
Committer: misc
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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