vulnerability

Microsoft Windows: CVE-2023-50387: MITRE: CVE-2023-50387 DNSSEC verification complexity can be exploited to exhaust CPU resources and stall DNS resolvers

Severity
8
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:C)
Published
Feb 13, 2024
Added
Feb 13, 2024
Modified
Sep 5, 2025

Description

Certain DNSSEC aspects of the DNS protocol (in RFC 4033, 4034, 4035, 6840, and related RFCs) allow remote attackers to cause a denial of service (CPU consumption) via one or more DNSSEC responses, aka the "KeyTrap" issue. One of the concerns is that, when there is a zone with many DNSKEY and RRSIG records, the protocol specification implies that an algorithm must evaluate all combinations of DNSKEY and RRSIG records.

Solutions

microsoft-windows-windows_server_2012-kb5034830microsoft-windows-windows_server_2012_r2-kb5034819microsoft-windows-windows_server_2016-1607-kb5034767microsoft-windows-windows_server_2019-1809-kb5034768microsoft-windows-windows_server_2022-21h2-kb5034770microsoft-windows-windows_server_2022-22h2-kb5034770microsoft-windows-windows_server_2022-23h2-kb5034769msft-kb5034809-2fa57b92-5154-4971-9913-d857fbe00d31
Title
Rapid7 Labs

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