This security bulletin contains one medium risk vulnerability.
Exploit availability: NoDescription
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists within the HTTP/2 implementation in Apache Tomcat that accepts streams with excessive numbers of SETTINGS frames and also permits clients to keep streams open without reading/writing request/response data. A remote attacker can exhaust all available threads on the server and perform denial of service attack.Mitigation
Install updates from vendor's website.Vulnerable software versions
Apache Tomcat: 8.5.0 - 8.5.37, 9.0.0-M1 - 9.0.14
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
How the attacker can exploit this vulnerability?
The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.