2021-34499 | Microsoft Windows DNS Server denial of service
|CVSS Meta Temp Score
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|Current Exploit Price (≈)
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|CTI Interest Score
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A vulnerability was found in Microsoft Windows (Operating System) and classified as critical. Affected by this issue is an unknown functionality of the component DNS Server. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. Impacted is availability. CVE summarizes:
Windows DNS Server Denial of Service Vulnerability This CVE ID is unique from CVE-2021-33745, CVE-2021-34442, CVE-2021-34444.
The weakness was disclosed 07/13/2021 as confirmed security guidance (Website). The advisory is shared for download at portal.msrc.microsoft.com. This vulnerability is handled as CVE-2021-34499 since 06/09/2021. The exploitation is known to be easy. The attack may be launched remotely. The successful exploitation needs a simple authentication. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 07/17/2021). The MITRE ATT&CK project declares the attack technique as T1499.
Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.
VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 5.7
Vendor Base Score (Microsoft): 6.5
Vendor Vector (Microsoft): 🔒
06/09/2021 CVE assigned
07/13/2021 +34 days Advisory disclosed
07/13/2021 +0 days Countermeasure disclosed
07/14/2021 +0 days VulDB entry created
07/17/2021 +3 days VulDB last updateVendor: https://www.microsoft.com/
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