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    Rewterz Threat Advisory – Multiple Adobe ColdFusion Vulnerabilities
    Severity High Analysis Summary CVE-2023-26361 CVSS:4.9 Adobe ColdFusion could allow a remote authenticated attacker to traverse directories on the system. An attacker could send a specially […]
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    Rewterz Threat Advisory – Multiple Microsoft Windows Layer 2 Tunneling Protocol (L2TP) Vulnerabilities

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    • Remote SOC
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    Rewterz penetration testing services help organizations determine if a cyber attacker can gain access to their critical assets while giving them detailed insights of the overall business impact of a cyber attack.

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    March 17, 2023
    March 17, 2023
    Rewterz Threat Alert – Chaos Ransomware – Active IOCs
    Severity High Analysis Summary Chaos is a customizable ransomware builder that emerged on June 9 2021 (in underground forums) by falsely marketing itself as the .NET […]
    March 17, 2023
    March 17, 2023
    Rewterz Threat Advisory – Multiple Adobe ColdFusion Vulnerabilities
    Severity High Analysis Summary CVE-2023-26361 CVSS:4.9 Adobe ColdFusion could allow a remote authenticated attacker to traverse directories on the system. An attacker could send a specially […]
    March 17, 2023
    March 17, 2023
    Rewterz Threat Alert – Ursnif Banking Trojan aka Gozi – Active IOCs
    Severity Medium Analysis Summary Ursnif banking trojan also known as Gozi and Dreambot has been around for more than 10 years. It gained popularity in 2015 […]

    Threat Insights

    16
    pdf-file (1)
    Annual Threat Intelligence Report 2022
    • Threat Advisories
    • Monthly Threat Insights
    • Threat Intelligence Reports
  • Why Rewterz?

    About Us

    Before Rewterz got its start, the market was in dire need of a specialized and dedicated information security company. It was nearly impossible for businesses to find a trustworthy provider that could truly cover all of their bases. We wanted to meet this need, giving companies across the globe a chance to get ahead while knowing that their data is in good hands.

    Read More

    play_btn_Smallplay_btn_hover_Small
    leadership

    Our Leadership

    Our leadership team brings together years of knowledge and experience in cybersecurity to drive our company's mission and vision. Our team is passionate about delivering high-quality products and services, leading by example and assisting our clients in securing their organization’s environment.
    help

    CSR

    At Rewterz, we believe that businesses have a responsibility to impact positively and contribute to the well-being of our communities as well as the planet. That's why we are committed to operating in a socially responsible and sustainable way.

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Rewterz
Rewterz Threat Alert – Bitter APT Threat Actors – Active IOCs
January 17, 2023
Rewterz
Rewterz Threat Advisory – Multiple Microsoft Windows Internet Key Exchange (IKE) Extension Vulnerabilities
January 17, 2023

Rewterz Threat Advisory – Multiple Microsoft Windows Layer 2 Tunneling Protocol (L2TP) Vulnerabilities

January 17, 2023

Severity

High

Analysis Summary

CVE-2023-21757 CVSS:7.5

Microsoft Windows is vulnerable to a denial of service, caused by a flaw in the Layer 2 Tunneling Protocol (L2TP). By sending a specially-crafted request, a remote attacker could exploit this vulnerability to cause a denial of service condition.

CVE-2023-21555 CVSS:8.1

Microsoft Windows could allow a remote attacker to execute arbitrary code on the system, caused by a flaw in the Layer 2 Tunneling Protocol (L2TP). By sending a specially-crafted request to a RAS server, an attacker could exploit this vulnerability to execute arbitrary code on the RAS server machine.

CVE-2023-21546 CVSS:8.1

Microsoft Windows could allow a remote attacker to execute arbitrary code on the system, caused by a flaw in the Layer 2 Tunneling Protocol (L2TP). By sending a specially-crafted request to a RAS server, an attacker could exploit this vulnerability to execute arbitrary code on the RAS server machine.

CVE-2023-21679 CVSS:8.1

Microsoft Windows could allow a remote attacker to execute arbitrary code on the system, caused by a flaw in the Layer 2 Tunneling Protocol (L2TP). By sending a specially-crafted request to a RAS server, an attacker could exploit this vulnerability to execute arbitrary code on the RAS server machine.

CVE-2023-21556 CVSS:8.1

Microsoft Windows could allow a remote attacker to execute arbitrary code on the system, caused by a flaw in the Layer 2 Tunneling Protocol (L2TP). By sending a specially-crafted request to a RAS server, an attacker could exploit this vulnerability to execute arbitrary code on the RAS server machine.

CVE-2023-21543 CVSS:8.1

Microsoft Windows could allow a remote attacker to execute arbitrary code on the system, caused by a flaw in the Layer 2 Tunneling Protocol (L2TP). By sending a specially-crafted request to a RAS server, an attacker could exploit this vulnerability to execute arbitrary code on the RAS server machine.

Impact

  • Denial of Service
  • Code Execution

Indicators Of Compromise

CVE

  • CVE-2023-21757
  • CVE-2023-21555
  • CVE-2023-21546
  • CVE-2023-21679
  • CVE-2023-21556
  • CVE-2023-21543

Affected Vendors

Microsoft

Affected Products

  • Microsoft Windows 7 SP1 x32
  • Microsoft Windows 7 SP1 x64
  • Microsoft Windows Server 2012
  • Microsoft Windows 8.1 x32
  • Microsoft Windows 8.1 x64
  • Microsoft Windows Server 2012 R2
  • Microsoft Windows RT 8.1Microsoft Windows 10 x32
  • Microsoft Windows 10 x64
  • Microsoft Windows Server 2016Microsoft Windows Server 2019
  • Microsoft Windows 10 1809 for x64-based Systems
  • Microsoft Windows 10 1809 for 32-bit Systems
  • Microsoft Windows 10 1809 for ARM64-based Systems
  • Microsoft Windows 10 1607 for 32-bit Systems
  • Microsoft Windows 10 1607 for x64-based Systems
  • Microsoft Windows 10 20H2 for 32-bit Systems
  • Microsoft Windows 10 20H2 for ARM64-based Systems
  • Microsoft Windows 10 20H2 for x64-based Systems
  • Microsoft Windows Server (Server Core installation) 2019
  • Microsoft Windows Server (Server Core installation) 2016
  • Microsoft Windows Server (Server Core installation) 2012 R2
  • Microsoft Windows Server (Server Core installation) 2012
  • Microsoft Windows Server for X64-based systems 2008 R2 SP1
  • Microsoft Windows Server for X64-based systems (Server Core installation) 2008 SP2
  • Microsoft Windows Server for 32-bit systems (Server Core installation) 2008 SP2
  • Microsoft Windows Server for 32-bit systems 2008 SP2Microsoft Windows Server 2022
  • Microsoft Windows Server (Server Core installation) 2022
  • Microsoft Windows Server for X64-based systems 2008 SP2
  • Microsoft Windows 10 21H2 for 32-bit Systems
  • Microsoft Windows 10 21H2 for ARM64-based Systems
  • Microsoft Windows 10 21H2 for x64-based Systems
  • Microsoft Windows Server 2022 Azure Edition Core Hotpatch
  • Microsoft Windows 11 22H2 for ARM64-based Systems
  • Microsoft Windows 11 22H2 for x64-based Systems
  • Microsoft Windows 10 22H2 for 32-bit Systems
  • Microsoft Windows 10 22H2 for ARM64-based Systems
  • Microsoft Windows 10 22H2 for x64-based Systems
  • Microsoft Windows 11 21H2 for ARM64-based Systems
  • Microsoft Windows 11 21H2 for x64-based Systems
  • Microsoft Windows Server for X64-based systems (Server Core installation) 2008 R2

Remediation

Use Microsoft Automatic Update to apply the appropriate patch for your system, or the Microsoft Security Update Guide to search for available patches.

CVE-2023-21757

CVE-2023-21555

CVE-2023-21546

CVE-2023-21679

CVE-2023-21556

CVE-2023-21543

Platform

  • Rewterz XDR
  • Rewterz Defense
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Managed Security Services

  • Managed Security Monitoring
  • Remote SOC
  • Onsite SOC
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Assess

  • Compromise Assessment
  • APT Assessment
  • Penetration Testing
  • Architecture Design & Review
  • Red Team Assessment
  • Purple Team Assessment
  • Social Engineering
  • Source Code Review

Transform

  • SOC Consultancy
  • SOC Maturity Assessment
  • SOC Model Evaluation
  • SOC Gap Analysis
  • SIEM Gap Analysis
  • SIEM Optimization
  • SOC Content Pack

Train

  • Simulated Cyber Attack Exercise
  • Tabletop Exercise
  • Security Awareness and Training

Respond

  • Incident Analysis
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Threat Insights

  • Threat Advisories
  • Monthly Threat Insights
  • Threat Intelligence Reports

Resources

  • Blog
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Connect With Us

  • Contact
  • Careers
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