Vulnerability identifier: #VU78135

Vulnerability risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-35298

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Windows Server
Operating systems & Components / Operating system
Windows
Operating systems & Components / Operating system
Microsoft IIS
Server applications / Web servers

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. A remote attacker can send a specially crafted packet to a targeted server utilizing the Server Name Indication (SNI) over HTTP Protocol Stack (http.sys) to process packets and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Windows Server: 2022 10.0.20348.202 - 2022 20H2

Windows: 11 21H2 10.0.22000.194, 11 22H2 10.0.22621.521

Microsoft IIS: 10.0

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External links
http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2023-35298

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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.