CVE-2021-24086
published 2021-02-25CVE-2021-24086: Windows TCP/IP Denial of Service Vulnerability Windows TCP/IP Denial of Service Vulnerability
high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
58.96%
99.0th percentile
Windows TCP/IP Denial of Service Vulnerability
Windows TCP/IP Denial of Service Vulnerability
Affected
35 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | windows_10_version_1507 | >= 10.0.0 < publication | publication |
| microsoft | windows_10_version_1607 | >= 10.0.0 < publication | publication |
| microsoft | windows_10_version_1803 | >= 10.0.0 < publication | publication |
| microsoft | windows_10_version_1809 | >= 10.0.0 < publication | publication |
| microsoft | windows_10_version_1909 | >= 10.0.0 < publication | publication |
| microsoft | windows_10_version_2004 | >= 10.0.0 < publication | publication |
| microsoft | windows_10_version_20h2 | >= 10.0.0 < publication | publication |
| microsoft | windows_7 | >= 6.1.0 < publication | publication |
| microsoft | windows_7_service_pack_1 | >= 6.1.0 < publication | publication |
| microsoft | windows_8.1 | >= 6.3.0 < publication | publication |
| microsoft | windows_server_2008_r2_service_pack_1 | >= 6.0.0 < publication | publication |
| microsoft | windows_server_2008_r2_service_pack_1 | >= 6.1.0 < publication | publication |
| microsoft | windows_server_2008_service_pack_2 | >= 6.0.0 < publication | publication |
| microsoft | windows_server_2012 | >= 6.2.0 < publication | publication |
| microsoft | windows_server_2012_r2 | >= 6.3.0 < publication | publication |
| microsoft | windows_server_2016 | >= 10.0.0 < publication | publication |
| microsoft | windows_server_2019 | >= 10.0.0 < publication | publication |
| microsoft | windows_server_version_2004 | >= 10.0.0 < publication | publication |
| microsoft | windows_server_version_20h2 | >= 10.0.0 < publication | publication |
| msrc | windows_10 | — | — |
| msrc | windows_10_version_1607 | — | — |
| msrc | windows_10_version_1803 | — | — |
| msrc | windows_10_version_1809 | — | — |
| msrc | windows_10_version_1909 | — | — |
| msrc | windows_10_version_2004 | — | — |
Detection & IOCsextracted from sources · hover to see the quote
- →Detect crafted IPv6 packets with multiple headers, invalid headers, or multiple fragment headers targeting Windows TCP/IP stack — these are the attack vectors for CVE-2021-24086 DoS. ↗
- →Monitor for IPv6 packets dropped due to truncated packets, invalid routing header position, or multiple fragment headers — these counters indicate active exploitation attempts against CVE-2021-24086. ↗
- →Alert on IPv6 fragmentation reassembly activity on Windows hosts — CVE-2021-24086 is triggered via IPv6 fragmentation bugs; disabling reassembly (reassemblylimit=0) is the workaround. ↗
- →Use edge/perimeter devices (not host-based firewalls) to block IPv6 fragmented packets — host-based firewalls are explicitly noted as insufficient protection for CVE-2021-24086. ↗
- →Scope exposure: Windows systems configured with ONLY IPv6 link-local addresses are not reachable by remote attackers for CVE-2021-24086 — focus monitoring on systems with routable IPv6 addresses. ↗
- ·The workaround command sets IPv6 reassembly limit to 0, dropping all out-of-order IPv6 fragments — this may cause legitimate packet loss and should be tested before deploying to production. ↗
- ·The default reassembly limit is 267748640; restoring it after patching requires running: Netsh int ipv6 set global reassemblylimit=267748640 ↗
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
cvelistv57.5HIGH
vendor_msrc9.8CRITICAL
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CVEList
Windows TCP/IP Denial of Service Vulnerability
cvelistv5·2021-02-25·CVSS 7.5
CVE-2021-24086 [HIGH] Windows TCP/IP Denial of Service Vulnerability
Windows TCP/IP Denial of Service Vulnerability
Windows TCP/IP Denial of Service Vulnerability
Microsoft
Windows TCP/IP Remote Code Execution Vulnerability
vendor_msrc·2021-02-09·CVSS 9.8
CVE-2021-24074 [CRITICAL] Windows TCP/IP Remote Code Execution Vulnerability
Windows TCP/IP Remote Code Execution Vulnerability
FAQ: Where can I find more information about this vulnerability?
Please see MSRC Blog regarding the TCP/IP vulnerabilities discussed in CVE-2021-24074, CVE-2021-24086, and CVE-2021-24094.
Windows TCP/IP: Windows TCP/IP
Microsoft: Microsoft
Impact: Remote Code Execution
Exploit Status: Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation More Likely;Older Software Release:Exploitation More Likely;DOS:N/A
Reference: https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB4601354
Reference: https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB4601345
Reference: https://support.microsoft.com/help/4601345
Reference: https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB4601331
Reference: https://
Microsoft
Windows TCP/IP Remote Code Execution Vulnerability
vendor_msrc·2021-02-09·CVSS 9.8
CVE-2021-24094 [CRITICAL] Windows TCP/IP Remote Code Execution Vulnerability
Windows TCP/IP Remote Code Execution Vulnerability
FAQ: Where can I find more information about this vulnerability?
Please see MSRC Blog regarding the TCP/IP vulnerabilities discussed in CVE-2021-24074, CVE-2021-24086, and CVE-2021-24094.
Windows TCP/IP: Windows TCP/IP
Microsoft: Microsoft
Impact: Remote Code Execution
Exploit Status: Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation More Likely;Older Software Release:Exploitation More Likely;DOS:N/A
Reference: https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB4601354
Reference: https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB4601345
Reference: https://support.microsoft.com/help/4601345
Reference: https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB4601331
Reference: https://
Microsoft
Windows TCP/IP Denial of Service Vulnerability
vendor_msrc·2021-02-09·CVSS 7.5
CVE-2021-24086 [CRITICAL] Windows TCP/IP Denial of Service Vulnerability
Windows TCP/IP Denial of Service Vulnerability
FAQ: Where can I find more information about this vulnerability?
Please see MSRC Blog regarding the TCP/IP vulnerabilities discussed in CVE-2021-24074, CVE-2021-24086, and CVE-2021-24094.
Windows TCP/IP: Windows TCP/IP
Microsoft: Microsoft
Impact: Denial of Service
Exploit Status: Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation More Likely;Older Software Release:Exploitation More Likely;DOS:N/A
Reference: https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB4601354
Reference: https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB4601345
Reference: https://support.microsoft.com/help/4601345
Reference: https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB4601331
Reference: https://catalog.
No detection rules found.
No public exploits indexed.
Bleepingcomputer
Zero-click Windows TCP/IP RCE impacts all systems with IPv6 enabled, patch now
blogs_bleepingcomputer·2024-08-14·CVSS 9.8
[CRITICAL] Zero-click Windows TCP/IP RCE impacts all systems with IPv6 enabled, patch now
## Zero-click Windows TCP/IP RCE impacts all systems with IPv6 enabled, patch now
## Sergiu Gatlan
As Microsoft explained in its Tuesday advisory, unauthenticated attackers can exploit the flaw remotely in low-complexity attacks by repeatedly sending IPv6 packets that include specially crafted packets.
Microsoft also shared its exploitability assessment for this critical vulnerability, tagging it with an "exploitation more likely" label, which means that threat actors could create exploit code to "consistently exploit the flaw in attacks."
"Moreover, Microsoft is aware of past instances of this type of vulnerability being exploited. This would make it an attractive target for attackers, and therefore more likely that exploits could be created," Redmond explains .
"As such, customers w
Securelist
IT threat evolution Q1 2021. Non-mobile statistics
blogs_securelist·2021-05-31
IT threat evolution Q1 2021. Non-mobile statistics
Table of Contents
Quarterly figures
Financial threats
Financial threat statistics
Ransomware programs
Quarterly trends and highlights
Number of new modifications
Number of users attacked by ransomware Trojans
Attack geography
Top 10 most common families of ransomware Trojans
Miners
Number of new modifications
Number of users attacked by miners
Attack geography
Vulnerable applications used by cybercriminals during cyber attacks
Attacks on macOS
Threat geography
IoT attacks
IoT threat statistics
SSH-based attacks
Threats loaded into traps
Attacks via web resources
Countries that are sources of web-based attacks: Top 10
Countries where users faced the greatest risk of online infection
Local threats
Countries where users faced the highest risk of local infection
Autho
Securelist
IT threat evolution Q1 2021. Non-mobile statistics
blogs_securelist·2021-05-31
IT threat evolution Q1 2021. Non-mobile statistics
Table of Contents
- Quarterly figures
- Financial threats
- Ransomware programs
- Miners
- Vulnerable applications used by cybercriminals during cyber attacks
- Attacks on macOS
- IoT attacks
- Attacks via web resources
- Local threats
Authors
- AMR
These statistics are based on detection verdicts of Kaspersky products received from users who consented to provide statistical data.
## Quarterly figures
According to Kaspersky Security Network, in Q1 2021:
- Kaspersky solutions blocked 2,023,556,082 attacks launched from online resources across the globe.
- 613,968,631 unique URLs were recognized as malicious by Web Anti-Virus components.
- Attempts to run malware designed to steal money via online access to bank accounts were stopped on the computers of 118,099 users.
- Ransomware att
Securelist
Kaspersky Security Bulletin 2020-2021. EU statistics
blogs_securelist·2021-05-26
Kaspersky Security Bulletin 2020-2021. EU statistics
Table of Contents
- Main figures
- Financial threats
- Ransomware programs
- Miners
- Vulnerable applications used by cybercriminals
- Attacks on macOS
- IoT attacks
- Attacks via web resources
- Local threats
- Phishing in the EU
Authors
- Kaspersky
All statistics in this report are from the global cloud service Kaspersky Security Network (KSN), which receives information from components in our security solutions. The data was obtained from users who have given their consent to it being sent to KSN. Millions of Kaspersky users around the globe assist us in this endeavor to collect information about malicious activity. The statistics in this report cover the period from May 2020 to April 2021, inclusive.
## Main figures
- 70% of Internet user computers in the EU experienced at least
Securelist
Kaspersky Security Bulletin 2020-2021. EU statistics
blogs_securelist·2021-05-26
Kaspersky Security Bulletin 2020-2021. EU statistics
Table of Contents
Main figures
Financial threats
Number of users attacked by banking malware
Threat geography
Ransomware programs
Number of users attacked by ransomware Trojans
Threat geography
Top 10 most common families of ransomware Trojans
Miners
Number of users attacked by miners in the EU
Threat geography
Vulnerable applications used by cybercriminals
Attacks on macOS
Threat geography
IoT attacks
IoT threat statistics
Malware loaded into honeypots
Attacks via web resources
Countries that are sources of web-based attacks
Countries where users faced the greatest risk of online infection
Top 20 malicious programs most actively used in online attacks
Local threats
Countries where users faced the highest risk of local infection
Top 20 malicious objects detected on
Unit42
Threat Brief: Windows IPv4 and IPv6 Stack Vulnerabilities (CVE-2021-24074, CVE-2021-24086 and CVE-2021-24094)
blogs_unit42·2021-02-09·CVSS 9.8
CVE-2021-24074 [CRITICAL] Threat Brief: Windows IPv4 and IPv6 Stack Vulnerabilities (CVE-2021-24074, CVE-2021-24086 and CVE-2021-24094)
## Executive Summary
For Microsoft’s Patch Tuesday for February 2021, the company released patches for 56 disclosed vulnerabilities, which include:
- CVE-2021-24086 and CVE-2021-24094: Two denial-of-service (DoS) vulnerabilities in the Windows IPv6 stack.
- CVE-2021-24074: Remote code execution (RCE) vulnerability in the Windows IPv4 stack.
CVE-2021-24086 was given the Common Vulnerability Scoring System (CVSS) score of 7.5/6.5 and an "Important" security rating from Microsoft.
CVE-2021-24094 and CVE-2021-24074 were given the CVSS score of 9.8/8.4 and a "Critical" security rating from Microsoft.
## CVE-2021-24086 and CVE-2021-24094 Overview
An attacker could send a number of crafted IPv6 packets (multiple headers, invalid header, multiple fragment headers, etc.), which would cause a
Tenable
Microsoft’s February 2021 Patch Tuesday Addresses 56 CVEs (CVE-2021-24074, CVE-2021-24094, CVE-2021-24086)
blogs_tenable·2021-02-09·CVSS 9.8
[CRITICAL] Microsoft’s February 2021 Patch Tuesday Addresses 56 CVEs (CVE-2021-24074, CVE-2021-24094, CVE-2021-24086)
## Cloud Exposure
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## Vulnerability Exposure
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## AI Exposure
Tenable AI Exposure Request a demo
## OT/IoT Exposure
Tenable OT Security Request a demo
## Identity Exposure
Tenable Identity Exposure Request a demo
## Business needs
Active Directory
AI Security Posture Management (AI-SPM)
AWS security
Azure security
Cloud Security Posture Man
Unit42
Threat Brief: Windows IPv4 and IPv6 Stack Vulnerabilities (CVE-2021-24074, CVE-2021-24086 and CVE-2021-24094)
blogs_unit42·2021-02-09·CVSS 9.8
CVE-2021-24074 [CRITICAL] Threat Brief: Windows IPv4 and IPv6 Stack Vulnerabilities (CVE-2021-24074, CVE-2021-24086 and CVE-2021-24094)
Threat Research Center
High Profile Threats
Vulnerabilities
## Threat Brief: Windows IPv4 and IPv6 Stack Vulnerabilities (CVE-2021-24074, CVE-2021-24086 and CVE-2021-24094)
Abisheik Ganesan
Published: February 9, 2021
High Profile Threats
Vulnerabilities
CVE-2021-24074
CVE-2021-24086
CVE-2021-24094
Microsoft
Windows
## Executive Summary
For Microsoft’s Patch Tuesday for February 2021, the company released patches for 56 disclosed vulnerabilities, which include:
CVE-2021-24086 and CVE-2021-24094 : Two denial-of-service (DoS) vulnerabilities in the Windows IPv6 stack.
CVE-2021-24074 : Remote code execution (RCE) vulnerability in the Windows IPv4 stack.
CVE-2021-24086 was given the Common Vulnerability Scoring System (CVSS) score of 7.5/6.5 and an "Important" security rat
Qualys
February 2021 Patch Tuesday – 56 Vulnerabilities, 11 Critical, Adobe
blogs_qualys·2021-02-09·CVSS 7.8
CVE-2021-24074 [HIGH] February 2021 Patch Tuesday – 56 Vulnerabilities, 11 Critical, Adobe
This month’s Microsoft Patch Tuesday addresses 56 vulnerabilities, of which 11 are rated as Critical. Adobe released patches today for Reader, Acrobat, Magento, Photoshop, Animate, Illustrator, and Dreamweaver.
## TCP/IP Trio
Microsoft released a set of fixes affecting Windows TCP/IP implementation that include two Critical Remote Code Execution (RCE) vulnerabilities (CVE-2021-24074 and CVE-2021-24094) and an Important Denial of Service (DoS) vulnerability (CVE-2021-24086). While there is no evidence that these vulnerabilities are exploited in wild, these vulnerabilities should be prioritized given their impact.
## Windows Fax Service
Microsoft released patches to fix a remote code execution vulnerability in Windows Fax Service (CVE-2021-24077). This vulnerability has a CVSSv3 base sco
Qualys
February 2021 Patch Tuesday – 56 Vulnerabilities, 11 Critical, Adobe | Qualys
blogs_qualys·2021-02-09·CVSS 7.8
CVE-2021-24074 [HIGH] February 2021 Patch Tuesday – 56 Vulnerabilities, 11 Critical, Adobe | Qualys
This month’s Microsoft Patch Tuesday addresses 56 vulnerabilities, of which 11 are rated as Critical. Adobe released patches today for Reader, Acrobat, Magento, Photoshop, Animate, Illustrator, and Dreamweaver.
### TCP/IP Trio
Microsoft released a set of fixes affecting Windows TCP/IP implementation that include two Critical Remote Code Execution (RCE) vulnerabilities (CVE-2021-24074 and CVE-2021-24094) and an Important Denial of Service (DoS) vulnerability (CVE-2021-24086). While there is no evidence that these vulnerabilities are exploited in wild, these vulnerabilities should be prioritized given their impact.
### Windows Fax Service
Microsoft released patches to fix a remote code execution vulnerability in Windows Fax Service (CVE-2021-24077). This vulnerability has a CVSSv3 base s
Unit42
Network Attack Trends: Attackers Leveraging High Severity and Critical Exploits (May-July 2020)
blogs_unit42·2020-09-15·CVSS 9.8
CVE-2021-24074 [CRITICAL] Network Attack Trends: Attackers Leveraging High Severity and Critical Exploits (May-July 2020)
Threat Research Center
Trend Reports
Vulnerabilities
## Network Attack Trends: Attackers Leveraging High Severity and Critical Exploits (May-July 2020)
Brock Mammen
Yue Guan
Yu Fu
Published: September 15, 2020
Trend Reports
Vulnerabilities
CVE-2021-24074
CVE-2021-24086
CVE-2021-24094
Microsoft
Windows
## Executive Summary
From May 1-July 21, 2020, Unit 42 researchers captured global network traffic from firewalls around the world and then analyzed the data to examine the latest network attack trends. The majority of attacks we observed were classified as high severity (56.7%), and nearly one quarter (23%) were classified as critical. The most common vulnerabilities exploited were CVE-2012-2311 and CVE-2012-1823 , both command injection vulnerabilities in PHP CGI scripts
2021-02-25
Published