Fedora Core 2 FEDORA-2004-150 Critical: Krb5 Multiple Buffer Overflows

Kerberos V5 is a trusted-third-party network authentication system,

which can improve your network's security by eliminating the insecure

practice of cleartext passwords.

Kerberos V5 is a trusted-third-party network authentication system,

which can improve your network's security by eliminating the insecure

practice of cleartext passwords.

Bugs have been fixed in the krb5_aname_to_localname library function. Specifically, buffer overflows were possible for all Kerberos versions up to and including 1.3.3. The krb5_aname_to_localname function translates a Kerberos principal name to a local account name, typically a UNIX username. This function is frequently used when performing authorization checks.

If configured with mappings from particular Kerberos principals to particular UNIX user names, certain functions called by krb5_aname_to_localname will not properly check the lengths of buffers used to store portions of the principal name. If configured to map principals to user names using rules, krb5_aname_to_localname would consistently write one byte past the end of a buffer allocated from the heap. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2004-0523 to this issue.

Only configurations which enable the explicit mapping or rules-based mapping functionality of krb5_aname_to_...