Vulnerability identifier: #VU18108
Vulnerability risk: Medium
CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]
CVE-ID:
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 an error within the mod_http2 module when processing update requests from http/1.1 to http/2, if this was not the first request on a connection. A remote attacker can send specially crafted requests to the affected server and perform denial of service attack.
Successful exploitation of the vulnerability requires that HTTP/2 protocol is enabled for a "http:" host or H2Upgrade is enabled for h2 on a "https:" host.
Mitigation
Install updates from vendor's website.
Vulnerable software versions
Apache HTTP Server: 2.4.34 - 2.4.38
External links
https://www.apache.org/dist/httpd/CHANGES_2.4
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.