These vulnerabilities are still unpatched in gentoo's mit-krb5 ebuild:
Applying patches listed in those advisories should resolve the problem.
2007-004 and 2007-005 are fixed in newer 1.5.x releases of mit-krb5.
I don't know which ebuild you're talking about, but SA 004 and 005 are fixed in app-crypt/mit-krb5-1.5.3 and SA 006 will be fixed with bug 191301.
*** This bug has been marked as a duplicate of bug 191301 ***