CVE-2021-26895
published 2021-03-11CVE-2021-26895: Windows DNS Server Remote Code Execution Vulnerability
PriorityP265critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
7.27%
94.0th percentile
Windows DNS Server Remote Code Execution Vulnerability
Affected
24 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | windows_server_2008 | — | — |
| microsoft | windows_server_2008 | — | — |
| microsoft | windows_server_2008_r2_service_pack_1 | >= 6.1.7601.0 < 6.1.7601.24566 | 6.1.7601.24566 |
| microsoft | windows_server_2008_service_pack_2 | >= 6.0.6003.0 < 6.0.6003.21070 | 6.0.6003.21070 |
| microsoft | windows_server_2012 | — | — |
| microsoft | windows_server_2012 | >= 6.2.9200.0 < 6.2.9200.23298 | 6.2.9200.23298 |
| microsoft | windows_server_2012_r2 | >= 6.3.9600.0 < 6.3.9600.19968 | 6.3.9600.19968 |
| microsoft | windows_server_2016 | — | — |
| microsoft | windows_server_2016 | — | — |
| microsoft | windows_server_2016 | — | — |
| microsoft | windows_server_2016 | >= 10.0.14393.0 < 10.0.14393.4283 | 10.0.14393.4283 |
| microsoft | windows_server_2019 | >= 10.0.17763.0 < 10.0.17763.1817 | 10.0.17763.1817 |
| microsoft | windows_server_version_2004 | >= 10.0.0 < 10.0.19043.867 | 10.0.19043.867 |
| microsoft | windows_server_version_20h2 | >= 10.0.0 < 10.0.19043.867 | 10.0.19043.867 |
| msrc | windows_server_2008_for_32-bit_systems_service_pack_2 | — | — |
| msrc | windows_server_2008_for_x64-based_systems_service_pack_2 | — | — |
| msrc | windows_server_2008_r2_for_x64-based_systems_service_pack_1 | — | — |
| msrc | windows_server_2012 | — | — |
| msrc | windows_server_2012_r2 | — | — |
| msrc | windows_server_2016 | — | — |
| msrc | windows_server_2019 | — | — |
| msrc | windows_server_version_1909 | — | — |
| msrc | windows_server_version_2004 | — | — |
| msrc | windows_server_version_20h2 | — | — |
Detection & IOCsextracted from sources · hover to see the quote
- →Vulnerability is only exploitable if the server is configured to be a DNS server — scope detection/hunting to systems with the DNS Server role enabled. ↗
- →A prerequisite for exploitation is that dynamic updates are enabled on the DNS server — audit DNS zones for dynamic update configuration as a detection/triage signal. ↗
- ·Dynamic updates must be enabled on the DNS server for the vulnerability to be exploitable — servers with dynamic updates disabled are not at risk. ↗
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.010.0CRITICALAV:N/AC:L/Au:N/C:C/I:C/A:C
vendor_msrc9.8CRITICAL
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VulDB
Microsoft Windows Server 20H2 up to Server 2016 DNS Server Remote Code Execution
vuldb·2026-08-21·CVSS 9.8
CVE-2021-26895 [CRITICAL] Microsoft Windows Server 20H2 up to Server 2016 DNS Server Remote Code Execution
A vulnerability, which was classified as very critical, was found in Microsoft Windows. This vulnerability affects unknown code of the component DNS Server. Executing a manipulation can lead to Remote Code Execution.
This vulnerability appears as CVE-2021-26895. The attack may be performed from remote. There is no available exploit.
It is best practice to apply a patch to resolve this issue.
GHSA
GHSA-8546-vjcf-9r45: Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26877, CVE-2021-26894, CVE-2021-26895, CVE-2021-26897
ghsa_unreviewed·2022-05-24·CVSS 9.8
CVE-2021-26893 [CRITICAL] GHSA-8546-vjcf-9r45: Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26877, CVE-2021-26894, CVE-2021-26895, CVE-2021-26897
Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26877, CVE-2021-26894, CVE-2021-26895, CVE-2021-26897.
GHSA
GHSA-86v8-8qp7-vj9r: Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26893, CVE-2021-26894, CVE-2021-26895, CVE-2021-26897
ghsa_unreviewed·2022-05-24·CVSS 9.8
CVE-2021-26877 [CRITICAL] CWE-94 GHSA-86v8-8qp7-vj9r: Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26893, CVE-2021-26894, CVE-2021-26895, CVE-2021-26897
Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26893, CVE-2021-26894, CVE-2021-26895, CVE-2021-26897.
GHSA
GHSA-wjv8-g83f-g23g: Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26877, CVE-2021-26893, CVE-2021-26894, CVE-2021-26897
ghsa_unreviewed·2022-05-24·CVSS 9.8
CVE-2021-26895 [CRITICAL] GHSA-wjv8-g83f-g23g: Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26877, CVE-2021-26893, CVE-2021-26894, CVE-2021-26897
Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26877, CVE-2021-26893, CVE-2021-26894, CVE-2021-26897.
GHSA
GHSA-5hxq-rvgg-jqff: Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26877, CVE-2021-26893, CVE-2021-26894, CVE-2021-26895
ghsa_unreviewed·2022-05-24·CVSS 9.8
CVE-2021-26897 [CRITICAL] GHSA-5hxq-rvgg-jqff: Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26877, CVE-2021-26893, CVE-2021-26894, CVE-2021-26895
Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26877, CVE-2021-26893, CVE-2021-26894, CVE-2021-26895.
GHSA
GHSA-96hx-qvj2-8fpm: Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26877, CVE-2021-26893, CVE-2021-26895, CVE-2021-26897
ghsa_unreviewed·2022-05-24·CVSS 9.8
CVE-2021-26894 [CRITICAL] GHSA-96hx-qvj2-8fpm: Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26877, CVE-2021-26893, CVE-2021-26895, CVE-2021-26897
Windows DNS Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26877, CVE-2021-26893, CVE-2021-26895, CVE-2021-26897.
Microsoft
Windows DNS Server Remote Code Execution Vulnerability
vendor_msrc·2021-03-09·CVSS 9.8
CVE-2021-26895 [CRITICAL] Windows DNS Server Remote Code Execution Vulnerability
Windows DNS Server Remote Code Execution Vulnerability
FAQ: Can this vulnerability by mitigated by enabling Secure Zone Updates?
Enabling Secure Zone Updates constrains the potential sources of the attack, but does not completely prevent it. For example, a malicious insider could attack a “secure zone update” DNS server from a domain-joined computer. This is only a partial mitigation.
Does this vulnerability impact just standalone DNS Primary Authoritative Server and not a DNS Server integrated with Active Directory?
This vulnerability impacts any DNS server. The surrounding configuration can limit possible vectors/sources for the attack, but proper mitigation requires this month’s security update patch.
FAQ: If my server is not configured to be a DNS server, it is vulnerable?
No, this v
No detection rules found.
No public exploits indexed.
Trendmicro
March Patch Tuesday: Fixes for Exchange Server, IE
blogs_trendmicro·2021-03-10·CVSS 9.1
[CRITICAL] March Patch Tuesday: Fixes for Exchange Server, IE
# March Patch Tuesday: Fixes for Exchange Server, IE
This month’s Patch Tuesday includes fixes already released for the Microsoft Exchange Server zero-day flaws attributed to Hafnium attacks.
By: Trend Micro
2021/03/10
Read time: ( words)
Save to Folio
This month’s Patch Tuesday features close to a hundred fixes, almost doubling last month’s total. The list includes patches already released for the Microsoft Exchange Server zero-day flaws attributed to Hafnium attacks.
Out of 89 patches released, 14 were rated Critical while the rest were deemed Important. Most of the critical vulnerabilities involve remote code execution (RCE) link except for an information disclosure bug. Fifteen of these were reported by the Zero Day Initiative (ZDI).
Microsoft Exchange Server Vulnerabilities
Th
Tenable
Microsoft’s March 2021 Patch Tuesday Addresses 82 CVEs (CVE-2021-26411)
blogs_tenable·2021-03-09·CVSS 8.8
[HIGH] Microsoft’s March 2021 Patch Tuesday Addresses 82 CVEs (CVE-2021-26411)
## Cloud Exposure
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## Vulnerability Exposure
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## AI Exposure
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## OT/IoT Exposure
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## Identity Exposure
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## Business needs
Active Directory
AI Security Posture Management (AI-SPM)
AWS security
Azure security
Cloud Security Posture Man
Talos
Microsoft Patch Tuesday for March 2021 — Snort rules and prominent vulnerabilities
blogs_talos·2021-03-09·CVSS 8.8
[HIGH] Microsoft Patch Tuesday for March 2021 — Snort rules and prominent vulnerabilities
By Jon Munshaw, with contributions from Nick Biasini.
Microsoft released its monthly security update Tuesday, disclosing 89 vulnerabilities across its suite of products, the most in any month so far this year.
There are 14 critical vulnerabilities as part of this release and one considered of “low” severity. The remainder are all “important.” Three of the critical vulnerabilities are the ones Microsoft disclosed last week in Exchange Server that the company said state-sponsored actors exploited in the wild to steal emails. Microsoft also announced Monday they were releasing patches for older versions of Exchange Server.
All organizations using the affected software should prevent external access to port 443 on Exchange Servers, or set up a VPN to provide external access to port 443. Thi
Talos
Microsoft Patch Tuesday for March 2021 — Snort rules and prominent vulnerabilities
blogs_talos·2021-03-09·CVSS 8.8
[HIGH] Microsoft Patch Tuesday for March 2021 — Snort rules and prominent vulnerabilities
## Microsoft Patch Tuesday for March 2021 — Snort rules and prominent vulnerabilities
By Jon Munshaw, with contributions from Nick Biasini.
Microsoft released its monthly security update Tuesday, disclosing 89 vulnerabilities across its suite of products, the most in any month so far this year.
There are 14 critical vulnerabilities as part of this release and one considered of “low” severity. The remainder are all “important.” Three of the critical vulnerabilities are the ones Microsoft disclosed last week in Exchange Server that the company said state-sponsored actors exploited in the wild to steal emails . Microsoft also announced Monday they were releasing patches for older versions of Exchange Server .
All organizations using the affected software should prevent external access to
Crowdstrike
March 2021 Patch Tuesday: Updates and Analysis
blogs_crowdstrike·CVSS 7.5
CVE-2026-20929 [HIGH] March 2021 Patch Tuesday: Updates and Analysis
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2021-03-11
Published