Source: cve@mitre.org
JavaMail API 1.1.3 through 1.3, as used by Apache Tomcat 5.0.16, allows remote attackers to read arbitrary files via a full pathname in the argument to the Download parameter. NOTE: Sun and Apache dispute this issue. Sun states: "The report makes references to source code and files that do not exist in the mentioned products.
Remote attackers can exploit a vulnerability in JavaMail API, potentially used by Apache Tomcat, to read arbitrary files on the server. This occurs due to insufficient input validation on the Download parameter, allowing attackers to specify full pathnames and access sensitive information. The impact could include data breaches and system compromise.
Step 1: Identify Target: The attacker identifies a vulnerable Apache Tomcat server using JavaMail API (versions 1.1.3 through 1.3).
Step 2: Craft Malicious Request: The attacker crafts an HTTP request to the Tomcat server, targeting the JavaMail API's functionality that utilizes the Download parameter.
Step 3: Inject Full Pathname: The attacker includes a full pathname to a target file (e.g., /etc/passwd, /WEB-INF/web.xml, or other sensitive files) as the value for the Download parameter.
Step 4: Server Processes Request: The Tomcat server, using the vulnerable JavaMail API, receives and processes the malicious request.
Step 5: File Read Operation: The JavaMail API, due to the lack of input validation, attempts to read the file specified by the attacker-controlled full pathname.
Step 6: Data Exfiltration: The server either returns the contents of the requested file directly in the HTTP response or logs the file's contents, allowing the attacker to obtain sensitive information.
The vulnerability stems from a lack of proper input validation in the JavaMail API, specifically when handling the Download parameter. The API fails to sanitize or restrict the input provided for the file path, allowing an attacker to specify an absolute path to any file accessible by the Tomcat process. This bypasses security measures and enables unauthorized file access. The root cause is a missing or inadequate check on the user-supplied file path within the JavaMail API's file retrieval logic. This allows a malicious actor to craft a request with a full file path, leading to the server reading and potentially returning the contents of the specified file. The issue is exacerbated by the API's use within a web server like Tomcat, which often handles sensitive data and configuration files.
This vulnerability is unlikely to be actively targeted by sophisticated APTs due to its age and specific requirements. However, it could be exploited by opportunistic attackers or used as part of a broader attack chain. There is no indication of this vulnerability being listed on the CISA KEV at this time.
Monitor web server logs (e.g., Tomcat access logs) for suspicious HTTP requests containing the Download parameter with full pathnames (e.g., /etc/passwd, /WEB-INF/web.xml).
Implement file integrity monitoring to detect unauthorized access or modification of sensitive files.
Analyze network traffic for unusual patterns, such as large file transfers or unexpected data exfiltration from the server.
Use intrusion detection/prevention systems (IDS/IPS) with rules specifically designed to detect path traversal attempts.
Review application source code (if available) for instances of the Download parameter usage and ensure proper input validation.
Upgrade to a patched version of JavaMail API or a version that doesn't include the vulnerable code (if applicable).
Implement robust input validation on the Download parameter to sanitize and restrict file paths. This includes validating the path against a whitelist of allowed files or directories and preventing the use of relative path components (e.g., ../).
Disable or remove the functionality that uses the Download parameter if it is not essential for the application's operation.
Apply the principle of least privilege: ensure the Tomcat process has minimal permissions and cannot access sensitive files.
Regularly update and patch all software components, including Tomcat and JavaMail, to address known vulnerabilities.
Implement a Web Application Firewall (WAF) to filter malicious requests and prevent path traversal attacks.