Vulnerability identifier: #VU51877

Vulnerability risk: Medium

CVSSv3.1: 7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:F/RL:O/RC:C]

CVE-ID: CVE-2021-28164

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
Jetty
Server applications / Web servers

Vendor: Eclipse

Description

The vulnerability allows a remote attacker to gain access to sensitive informatoin.

The vulnerability exists due to insufficient validation of user-supplied input when processing special characters, passed via URI. A remote attacker can use %2e or %2e%2e segments to access protected resources within the WEB-INF directory.

Example:

http://[host]/context/%2e/WEB-INF/web.xml

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Jetty: 9.4.37.v20210219 - 9.4.38.v20210224

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External links
http://github.com/eclipse/jetty.project/security/advisories/GHSA-v7ff-8wcx-gmc5
http://bugs.eclipse.org/bugs/show_bug.cgi?id=572219

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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. However, a fully functional exploit for this vulnerability is available.