Security restrictions bypass in Undertow

1) Input validation error

EUVDB-ID: #VU27296

Risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-1757

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass security restrictions.

The vulnerability exists due to insufficient validation of user-supplied input in Servlet container that causes the servletPath to incorrectly normalize data by truncating the path after semicolon. A remote attacker can pass specially crafted input to the application and bypass security restrictions

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Undertow: 1.0.0 - 2.0.30

External links

http://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-1757

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.