Microsoft Response to Distributed Denial of Service (DDoS) Attacks against HTTP/2

2023-10-1007:00:00

Microsoft Security Response Center

msrc.microsoft.com

microsoft

ddos

http/2

cve-2023-44487

vulnerability

industry partners

investigation

disclosure

mitigation plan

CVSS3

7.5

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

AI Score

7.5

Confidence

High

EPSS

0.816

Percentile

98.4%

JSON

Summary Beginning in September 2023, Microsoft was notified by industry partners about a newly identified Distributed Denial-of-Service (DDoS) attack technique being used in the wild targeting HTTP/2 protocol. This vulnerability (CVE-2023-44487) impacts any internet exposed HTTP/2 endpoints. As an industry leader, Microsoft promptly opened an investigation and subsequently began working with industry partners for a coordinated disclosure and mitigation plan.