#VU55417 Improper Authentication in Apache Tomcat - CVE-2021-30640

Vulnerability identifier: #VU55417

Vulnerability risk: Medium

CVSSv4.0: 4.8 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-30640

CWE-ID: CWE-287

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Apache Tomcat
Server applications / Web servers

Vendor: Apache Foundation

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 - 7.0.108, 8.5.0 - 8.5.65, 9.0.0-M1 - 9.0.45, 10.0.0-M1 - 10.0.5

---

External links
https://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.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.