• Home
  • Cyber Crime
  • Cyber warfare
  • APT
  • Data Breach
  • Deep Web
  • Digital ID
  • Hacking
  • Hacktivism
  • Intelligence
  • Internet of Things
  • Laws and regulations
  • Malware
  • Mobile
  • Reports
  • Security
  • Social Networks
  • Terrorism
  • ICS-SCADA
  • POLICIES
  • Contact me
MUST READ

Coyote malware is first-ever malware abusing Windows UI Automation

 | 

SonicWall fixed critical flaw in SMA 100 devices exploited in Overstep malware attacks

 | 

DSPM & AI Are Booming: $17.87B and $4.8T Markets by 2033

 | 

Stealth backdoor found in WordPress mu-Plugins folder

 | 

U.S. CISA adds CrushFTP, Google Chromium, and SysAid flaws to its Known Exploited Vulnerabilities catalog

 | 

U.S. CISA urges FCEB agencies to fix two Microsoft SharePoint flaws immediately and added them to its Known Exploited Vulnerabilities catalog

 | 

Sophos fixed two critical Sophos Firewall vulnerabilities

 | 

French Authorities confirm XSS.is admin arrested in Ukraine

 | 

Microsoft linked attacks on SharePoint flaws to China-nexus actors

 | 

Cisco confirms active exploitation of ISE and ISE-PIC flaws

 | 

SharePoint under fire: new ToolShell attacks target enterprises

 | 

CrushFTP zero-day actively exploited at least since July 18

 | 

Hardcoded credentials found in HPE Aruba Instant On Wi-Fi devices

 | 

MuddyWater deploys new DCHSpy variants amid Iran-Israel conflict

 | 

U.S. CISA urges to immediately patch Microsoft SharePoint flaw adding it to its Known Exploited Vulnerabilities catalog

 | 

Microsoft issues emergency patches for SharePoint zero-days exploited in "ToolShell" attacks

 | 

SharePoint zero-day CVE-2025-53770 actively exploited in the wild

 | 

Singapore warns China-linked group UNC3886 targets its critical infrastructure

 | 

U.S. CISA adds Fortinet FortiWeb flaw to its Known Exploited Vulnerabilities catalog

 | 

SECURITY AFFAIRS MALWARE NEWSLETTER ROUND 54

 | 
  • Home
  • Cyber Crime
  • Cyber warfare
  • APT
  • Data Breach
  • Deep Web
  • Digital ID
  • Hacking
  • Hacktivism
  • Intelligence
  • Internet of Things
  • Laws and regulations
  • Malware
  • Mobile
  • Reports
  • Security
  • Social Networks
  • Terrorism
  • ICS-SCADA
  • POLICIES
  • Contact me
  • Home
  • Breaking News
  • Hacking
  • Microsoft accidentally reveals Wormable Win SMBv3 CVE-2020-0796 Flaw

Microsoft accidentally reveals Wormable Win SMBv3 CVE-2020-0796 Flaw

Pierluigi Paganini March 10, 2020

Today Microsoft accidentally leaked info about a new wormable vulnerability (CVE-2020-0796) in the Microsoft Server Message Block (SMB) protocol.

Today Microsoft accidentally leaked info on a security update for a wormable vulnerability in the Microsoft Server Message Block (SMB) protocol.

The issue, tracked as CVE-2020-0796, is pre- remote code execution vulnerability that resides in the Server Message Block 3.0 (SMBv3) network communication protocol, the IT giant will not address the issue as part of the March 2020 Patch Tuesday.

CVE-2020-0796 – a "wormable" SMBv3 vulnerability.
Great…
😂 pic.twitter.com/E3uPZkOyQN

— MalwareHunterTeam (@malwrhunterteam) March 10, 2020

Technical details of the CVE-2020-0796 vulnerability have been disclosed, but security firms Cisco Talos and Fortinet published a description of the issue on their websites.

The vulnerability is caused by an error in the way SMBv3 handles maliciously crafted compressed data packets, a remote, unauthenticated attacker could exploit the flaw to execute arbitrary code within the context of the application.

“This indicates an attack attempt to exploit a Buffer Overflow Vulnerability in Microsoft SMB Servers. The vulnerability is due to an error when the vulnerable software handles a maliciously crafted compressed data packet. A remote, unauthenticated attacker can exploit this to execute arbitrary code within the context of the application.” reads the advisory published by Fortinet.

The CVE-2020-0796 vulnerability affects devices running Windows 10 Version 1903, Windows Server Version 1903 (Server Core installation), Windows 10 Version 1909, and Windows Server Version 1909 (Server Core installation). According to Fortinet other Microsoft versions should be affected.

The knowledge of the existence of a wormable flaw impacting SMB protocol is alerting the experts that fear a new wave of WannaCry and NotPetya-like attacks.

Waiting for a security update that will address the issue, experts at Cisco Talos recommend disabling SMBv3 compression and blocking the 445 TCP port on client computers and firewalls to mitigate the issue.

https://twitter.com/NiallNSec/status/1237474263600332802

According to BleepingComputer, although an official way of disabling SMBv3 compression was not shared by Microsoft, Foregenix Solutions Architect Niall Newman was able to find after analyzing the Srv2.sys file that it can be done by

1. Going to HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\LanManWorkstation\Parameters
2. Creating a DWORD value called
3. Setting its value to 0.”

Update March 10, 2020

“Microsoft is aware of a remote code execution vulnerability in the way that the Microsoft Server Message Block 3.1.1 (SMBv3) protocol handles certain requests. An attacker who successfully exploited the vulnerability could gain the ability to execute code on the target SMB Server or SMB Client.” reads the advisory published by Microsoft.

“To exploit the vulnerability against an SMB Server, an unauthenticated attacker could send a specially crafted packet to a targeted SMBv3 Server. To exploit the vulnerability against an SMB Client, an unauthenticated attacker would need to configure a malicious SMBv3 Server and convince a user to connect to it.”

[adrotate banner=”9″] [adrotate banner=”12″]

Pierluigi Paganini

(SecurityAffairs – hacking, CVE-2020-0796)

[adrotate banner=”5″]

[adrotate banner=”13″]


facebook linkedin twitter

Hacking hacking news it security it security news Microsoft Pierluigi Paganini Security Affairs Security News SMB

you might also like

Pierluigi Paganini July 24, 2025
Coyote malware is first-ever malware abusing Windows UI Automation
Read more
Pierluigi Paganini July 24, 2025
SonicWall fixed critical flaw in SMA 100 devices exploited in Overstep malware attacks
Read more

leave a comment

newsletter

Subscribe to my email list and stay
up-to-date!

    recent articles

    Coyote malware is first-ever malware abusing Windows UI Automation

    Malware / July 24, 2025

    SonicWall fixed critical flaw in SMA 100 devices exploited in Overstep malware attacks

    Security / July 24, 2025

    DSPM & AI Are Booming: $17.87B and $4.8T Markets by 2033

    Security / July 24, 2025

    Stealth backdoor found in WordPress mu-Plugins folder

    Malware / July 24, 2025

    U.S. CISA adds CrushFTP, Google Chromium, and SysAid flaws to its Known Exploited Vulnerabilities catalog

    Hacking / July 24, 2025

    To contact me write an email to:

    Pierluigi Paganini :
    pierluigi.paganini@securityaffairs.co

    LEARN MORE

    QUICK LINKS

    • Home
    • Cyber Crime
    • Cyber warfare
    • APT
    • Data Breach
    • Deep Web
    • Digital ID
    • Hacking
    • Hacktivism
    • Intelligence
    • Internet of Things
    • Laws and regulations
    • Malware
    • Mobile
    • Reports
    • Security
    • Social Networks
    • Terrorism
    • ICS-SCADA
    • POLICIES
    • Contact me

    Copyright@securityaffairs 2024

    We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept All”, you consent to the use of ALL the cookies. However, you may visit "Cookie Settings" to provide a controlled consent.
    Cookie SettingsAccept All
    Manage consent

    Privacy Overview

    This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities...
    Necessary
    Always Enabled
    Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
    Non-necessary
    Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.
    SAVE & ACCEPT