Authentication bypass in Apache Tomcat JNDI Realm

1) Improper Authentication

EUVDB-ID: #VU55417

Risk: Medium

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

CVE-ID: CVE-2021-30640

CWE-ID: CWE-287 - Improper Authentication

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to an error in the JNDI Realm when processing authentication requests. A remote attacker can authenticate using variations of a valid user name and bypass some of the protection provided by the LockOut Realm.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Apache Tomcat: 7.0.0 - 10.0.5

External links

http://lists.apache.org/thread.html/r59f9ef03929d32120f91f4ea7e6e79edd5688d75d0a9b65fd26d1fe8%40%3Cannounce.tomcat.apache.org%3E

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.