CVE-2021-41079: Apache Tomcat DoS with unexpected TLS packet
A flaw was found in Apache Tomcat. When Tomcat was configured to use NIO+OpenSSL or NIO2+OpenSSL for TLS, a specially crafted packet can trigger an infinite loop, resulting in a denial of service. The highest threat from this vulnerability is to system availability.
Other sources
Apache Tomcat 8.5.0 to 8.5.63, 9.0.0-M1 to 9.0.43 and 10.0.0-M1 to 10.0.2 did not properly validate incoming TLS packets. When Tomcat was configured to use NIO+OpenSSL or NIO2+OpenSSL for TLS, a specially crafted packet could be used to trigger an infinite loop resulting in a denial of service.
Apache Tomcat did not properly validate incoming TLS packets. When Tomcat was configured to use NIO+OpenSSL or NIO2+OpenSSL for TLS, a specially crafted packet could be used to trigger an infinite loop resulting in a denial of service. This issue affects the version of Apache Tomcat 10.0.0-M1 to 10.0.2; 9.0.0-M1 to 9.0.43; 8.5.0 to 8.5.63.
Upstream commits: Tomcat 10.0.4: https://github.com/apache/tomcat/commit/34115fb3c83f6cd97772232316a492a4cc5729e0 Tomcat 9.0.44: https://github.com/apache/tomcat/commit/d4b340fa8feaf55831f9a59350578f7b6ca048b8 Tomcat 8.5.64: https://github.com/apache/tomcat/commit/b90d4fc1ff44f30e4b3aba622ba6677e3f003822
Reference: https://lists.apache.org/thread.html/rccdef0349fdf4fb73a4e4403095446d7fe6264e0a58e2df5c6799434%40%3Cannounce.tomcat.apache.org%3E
— Red Hat
Apache Tomcat is vulnerable to a denial of service, caused by improper input validation of TLS packets. By sending a specially-crafted TLS packet, a remote attacker could exploit this vulnerability to cause the application to enter into an infinite loop.
— IBM
Affected Software
Event History
Parent advisories
This vulnerability appears in the following advisories.
Frequently Asked Questions
What is the vulnerability ID?
The vulnerability ID is CVE-2021-41079.
What is the severity of CVE-2021-41079?
The severity of CVE-2021-41079 is high with a CVSS score of 7.5.
What is the affected software?
The affected software includes Apache Tomcat versions 8.5.0 to 8.5.63, 9.0.0-M1 to 9.0.43, and 10.0.0-M1 to 10.0.2.
How can I fix CVE-2021-41079?
To fix CVE-2021-41079, you need to update Apache Tomcat to version 10.0.4, 9.0.44, or 8.5.64, depending on the version you are using.
Where can I find more information about CVE-2021-41079?
You can find more information about CVE-2021-41079 in the references section.