Denial of service in Undertow

1) Resource exhaustion

EUVDB-ID: #VU51517

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-2020-27782

CWE-ID: CWE-400 - Resource exhaustion

Exploit availability: No

Description

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

The vulnerability exists due to application does not properly control consumption of internal resources within the Undertow AJP connector. Malicious requests and abrupt connection closes could be triggered by an attacker using query strings with non-RFC compliant characters resulting in a denial of service. A remote attacker can trigger resource exhaustion and perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Undertow: 2.0.0 - 2.2.3

External links

http://bugzilla.redhat.com/show_bug.cgi?id=1901304

Q & A

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.