CVE-2023-41080: Apache Tomcat Open Redirect Vulnerability

Web servers are at the heart of our online experiences. They serve web pages, host web applications, and handle millions of requests daily. Just like any other complex system, they aren’t immune to vulnerabilities. Among the known web servers, Apache Tomcat stands tall as a significant player. However, even giants can trip, and this time, it’s due to an open redirect vulnerability, aptly tagged as CVE-2023-41080.

Open redirects are no strangers to the world of web vulnerabilities. An open redirect is when a malicious website tricks visitors into clicking a link that seems harmless or legitimate but redirects them to a site with malicious intent. This can lead to phishing attacks, data theft, and a general breach of trust.

In the case of Apache Tomcat, if the ROOT (default) web application utilizes FORM authentication, the server becomes susceptible. Attackers can craft specific URLs which, when accessed, will bounce users off to a URL of the attacker’s choice. A genuine-looking link might redirect a user to a webpage designed to steal their credentials or inject malware onto their systems.

Yiheng Cao, a security researcher, spotted this flaw. Bringing vulnerabilities to light is crucial in the digital age, as it allows companies and developers to patch up the issues before they become widespread.

If you’re running any of the following versions of Apache Tomcat, your system may be vulnerable:

• Apache Tomcat 11.0.0-M1 to 11.0.0-M10
• Apache Tomcat 10.1.0-M1 to 10.1.12
• Apache Tomcat 9.0.0-M1 to 9.0.79
• Apache Tomcat 8.5.0 to 8.5.92

The broader the version spectrum, the greater the number of potential victims. This vulnerability stretches across several major versions, making its potential impact quite extensive.

Fear not, for every vulnerability, there’s usually a mitigation path. For CVE-2023-41080, the path is straightforward: update your Apache Tomcat. The following versions have been patched to defend against this open redirect vulnerability:

• Apache Tomcat 11.0.0-M11 or later
• Apache Tomcat 10.1.13 or later
• Apache Tomcat 9.0.80 or later
• Apache Tomcat 8.5.93 or later

If you’re using any of the vulnerable versions, it’s recommended to upgrade as soon as possible.