Apache Tomcat before 6.0.39, 7.x before 7.0.50, and 8.x before 8.0.0-RC10 allows attackers to obtain "Tomcat internals" information by leveraging the presence of an untrusted web application with a context.xml, web.xml, *.jspx, *.tagx, or *.tld XML document containing an external entity declaration in conjunction with an entity reference, related to an XML External Entity (XXE) issue.

Apache Tomcat before 6.0.39, 7.x before 7.0.50, and 8.x before 8.0.0-RC10 processes chunked transfer coding without properly handling (1) a large total amount of chunked data or (2) whitespace characters in an HTTP header value within a trailer field, which allows remote attackers to cause a denial of service by streaming data. NOTE: this vulnerability exists because of an incomplete fix for CVE-2012-3544.

Apache Tomcat before 6.0.39, 7.x before 7.0.47, and 8.x before 8.0.0-RC3, when an HTTP connector or AJP connector is used, does not properly handle certain inconsistent HTTP request headers, which allows remote attackers to trigger incorrect identification of a request's length and conduct request-smuggling attacks via (1) multiple Content-Length headers or (2) a Content-Length header and a "Transfer-Encoding: chunked" header. NOTE: this vulnerability exists because of an incomplete fix for CVE-2005-2090.

Cross-site request forgery (CSRF) vulnerability in the Manager application in Apache Tomcat 5.5.25 and earlier allows remote attackers to hijack the authentication of administrators for requests that manipulate application deployment via the POST method, as demonstrated by a /manager/html/undeploy?path= URI. NOTE: the vendor disputes the significance of this report, stating that "the Apache Tomcat Security team has not accepted any reports of CSRF attacks against the Manager application ... as they require a reckless system administrator.

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 before 5.x allows remote attackers to cause a denial of service (application crash) via a crafted AJP12 packet to TCP port 8007.

The default servlet (org.apache.catalina.servlets.DefaultServlet) in Tomcat 4.0.4 and 4.1.10 and earlier allows remote attackers to read source code for server files via a direct request to the servlet.