CVE-2024-49091 Overview
CVE-2024-49091 is a remote code execution vulnerability affecting the Windows Domain Name Service (DNS) role across supported Windows Server releases. Microsoft published the advisory on December 12, 2024. The flaw is categorized under [CWE-591] (sensitive data storage in improperly locked memory) and allows an authenticated attacker with high privileges to trigger code execution over the network against a vulnerable DNS server. Successful exploitation impacts confidentiality, integrity, and availability of the target host.
Critical Impact
An attacker who successfully exploits CVE-2024-49091 can execute arbitrary code against the Windows DNS service, potentially compromising domain infrastructure that supports authentication, name resolution, and Active Directory operations.
Affected Products
- Microsoft Windows Server 2012 and Windows Server 2012 R2
- Microsoft Windows Server 2016, 2019, 2022, and Windows Server 2022 23H2
- Microsoft Windows Server 2025
Discovery Timeline
- 2024-12-12 - CVE-2024-49091 published to NVD alongside the Microsoft advisory
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-49091
Vulnerability Analysis
The vulnerability resides in the Windows DNS Server role, a core service that resolves names for Active Directory domains. Microsoft categorizes the flaw as a remote code execution issue tied to [CWE-591], which describes sensitive data being stored in memory that is not properly locked or protected. When the DNS service processes crafted input under specific conditions, unprotected memory contents can be manipulated to influence execution flow.
Exploitation requires network access to the DNS service and high privileges on the target environment. No user interaction is needed. Because the DNS role frequently runs on domain controllers, code execution in this context can affect directory services that depend on it for name resolution and service location.
Root Cause
The root cause is aligned with [CWE-591]: sensitive data handled by the DNS service is placed in memory regions without adequate protection, allowing an attacker with the required privileges to influence how that data is processed. Microsoft has not published detailed internals; the vendor advisory should be consulted for authoritative technical specifics.
Attack Vector
The attack vector is network-based against the DNS service listener. The attacker must already hold high-privileged access within the environment before triggering the vulnerable code path. Once conditions are met, the attacker can achieve remote code execution against the DNS Server process, which typically runs with SYSTEM-level privileges.
No public proof-of-concept is available, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog. The current EPSS probability is 1.677% (74.7th percentile), indicating measurable but not widespread exploitation likelihood.
See the Microsoft Security Update Guide for authoritative technical details.
Detection Methods for CVE-2024-49091
Indicators of Compromise
- Unexpected crashes, restarts, or access violations in the dns.exe process on Windows Server hosts running the DNS role.
- Anomalous outbound network activity or child process creation originating from dns.exe.
- New or unusual DNS zones, records, or configuration changes made by high-privileged accounts outside normal change windows.
Detection Strategies
- Monitor DNS Server event logs and Windows Application logs for service crashes, faulting module entries referencing DNS binaries, and unexpected restarts.
- Use endpoint telemetry to flag process creation where dns.exe spawns command shells, scripting engines, or LOLBins.
- Correlate authentication logs for high-privileged accounts with DNS administrative changes to identify misuse of credentials required for exploitation.
Monitoring Recommendations
- Enable Sysmon or equivalent process-creation logging on domain controllers and standalone DNS servers, forwarding data to a central SIEM.
- Track patch state across all Windows Server systems running the DNS Server role and alert on hosts that remain unpatched.
- Baseline normal DNS server behavior (memory footprint, thread counts, listener activity) so that deviations can be identified quickly.
How to Mitigate CVE-2024-49091
Immediate Actions Required
- Apply the Microsoft security updates for CVE-2024-49091 to all affected Windows Server versions running the DNS role.
- Audit which accounts hold the high privileges required for exploitation and reduce membership in privileged directory groups.
- Restrict administrative network paths to DNS servers so that only authorized management hosts can reach the service.
Patch Information
Microsoft has released fixes through the December 2024 security update cycle for Windows Server 2012, 2012 R2, 2016, 2019, 2022, 2022 23H2, and Windows Server 2025. Refer to the Microsoft Security Update Guide for build-specific KB articles and download packages.
Workarounds
- No official workaround has been published by Microsoft; patching is the required remediation.
- Where patching must be delayed, apply network segmentation and firewall rules to limit exposure of the DNS service to trusted management networks.
- Enforce tiered administration so that only Tier 0 accounts can reach the DNS management surface, reducing the population of accounts that could trigger the vulnerability.
# Verify installed updates on a Windows Server DNS host
Get-HotFix | Sort-Object -Property InstalledOn -Descending
# Confirm the DNS Server role and service state
Get-WindowsFeature -Name DNS
Get-Service -Name DNS
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
