Vulnerability identifier: #VU28113

Vulnerability risk: Medium

CVSSv3.1: 6.9 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:U/RC:C]

CVE-ID: N/A

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Windows Server
Operating systems & Components / Operating system

Vendor: Microsoft

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input when processing DNS requests. While resolving a name from the attacker client, for each referral record found, the resolver contacts the victim domain. This action can generate a large number of communications between the recursive resolver and the victim's authoritative DNS server to cause a Distributed Denial of Service (DDoS) attack.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

Windows Server: 2008 - 2019 1909

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External links
http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200009

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.