Description

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.

Mitigation

We recommend upgrading to a version of this component that is not vulnerable to this specific issue.

Related links:

• http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2009-0580

• http://tomcat.apache.org/security-4.html

• http://tomcat.apache.org/security-5.html

• http://tomcat.apache.org/security-6.html

• https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2009-0580