Vulnerability identifier: #VU56634

Vulnerability risk: Medium

CVSSv3.1: 5.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-41079

CWE-ID: CWE-835

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 perform a denial of service (DoS) attack.

The vulnerability exists due to infinite loop when processing certain TLS packets. A remote attacker can send a specially crafted packet to the application, consume all available system resources and cause denial of service conditions.

Successful exploitation of vulnerability requires that Apache Tomcat is configured to use NIO+OpenSSL or NIO2+OpenSSL for TLS.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Apache Tomcat: 10.0.0 - 10.0.2, 9.0.0 - 9.0.43, 8.5.0 - 8.5.63

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External links
http://lists.apache.org/thread.html/rccdef0349fdf4fb73a4e4403095446d7fe6264e0a58e2df5c6799434%40%3Cannounce.tomcat.apache.org%3E

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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.