The default configuration of Apache Tomcat 6.x does not include the HTTPOnly flag in a Set-Cookie header, which makes it easier for remote attackers to hijack a session via script access to a cookie.

Apache Tomcat 5.5.0 through 5.5.29, 6.0.0 through 6.0.27, and 7.0.0 beta does not properly handle an invalid Transfer-Encoding header, which allows remote attackers to cause a denial of service (application outage) or obtain sensitive information via a crafted header that interferes with "recycling of a buffer."

Apache Tomcat 5.5.0 through 5.5.29 and 6.0.0 through 6.0.26 might allow remote attackers to discover the server's hostname or IP address by sending a request for a resource that requires (1) BASIC or (2) DIGEST authentication, and then reading the realm field in the WWW-Authenticate header in the reply.

The autodeployment process in Apache Tomcat 5.5.0 through 5.5.28 and 6.0.0 through 6.0.20, when autoDeploy is enabled, deploys appBase files that remain from a failed undeploy, which might allow remote attackers to bypass intended authentication requirements via HTTP requests.

Directory traversal vulnerability in Apache Tomcat 5.5.0 through 5.5.28 and 6.0.0 through 6.0.20 allows remote attackers to create or overwrite arbitrary files via a .. (dot dot) in an entry in a WAR file, as demonstrated by a ../../bin/catalina.bat entry.

Directory traversal vulnerability in Apache Tomcat 5.5.0 through 5.5.28 and 6.0.0 through 6.0.20 allows remote attackers to delete work-directory files via directory traversal sequences in a WAR filename, as demonstrated by the ...war filename.

The Windows installer for Apache Tomcat 6.0.0 through 6.0.20, 5.5.0 through 5.5.28, and possibly earlier versions uses a blank default password for the administrative user, which allows remote attackers to gain privileges.

Apache Tomcat 4.1.0 through 4.1.39, 5.5.0 through 5.5.27, 6.0.0 through 6.0.18, and possibly earlier versions normalizes the target pathname before filtering the query string when using the RequestDispatcher method, which allows remote attackers to bypass intended access restrictions and conduct directory traversal attacks via .. (dot dot) sequences and the WEB-INF directory in a Request.

Apache Tomcat 4.1.0 through 4.1.39, 5.5.0 through 5.5.27, and 6.0.0 through 6.0.18, when the Java AJP connector and mod_jk load balancing are used, allows remote attackers to cause a denial of service (application outage) via a crafted request with invalid headers, related to temporary blocking of connectors that have encountered errors, as demonstrated by an error involving a malformed HTTP Host header.

Apache Tomcat 4.1.0 through 4.1.39, 5.5.0 through 5.5.27, and 6.0.0 through 6.0.18, when FORM authentication is used, allows remote attackers to enumerate valid usernames via requests to /j_security_check with malformed URL encoding of passwords, related to improper error checking in the (1) MemoryRealm, (2) DataSourceRealm, and (3) JDBCRealm authentication realms, as demonstrated by a % (percent) value for the j_password parameter.