Vulnerability identifier: #VU14913

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-2018-11763

CWE-ID: CWE-399

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Apache HTTP Server
Server applications / Web servers

Vendor: Apache Foundation

Description

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

The vulnerability exists due to incorrect handling of large SETTINGS frames in HTTP/2 connections. A remote attacker can repeatedly send large SETTINGS frames within an established HTTP/2 connection and consume all available threads and CPU time.

Successful exploitation of the vulnerability may allow an attacker to perform a denial of service (DoS) attack.

Mitigation
Update to version 2.4.35.

Vulnerable software versions

Apache HTTP Server: 2.4.17 - 2.4.34

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External links
http://httpd.apache.org/security/vulnerabilities_24.html

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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.