Server Side Request Forgery (SSRF) exists in the Print My Blog plugin before 1.6.7 for WordPress via the site parameter.
dumpco.re/bugs/wp-plugin-print-my-blog-ssrf
github.com/mnelson4/printmyblog/commit/8584a2839a541eb29fca64252e388c827af3ec21
plugins.trac.wordpress.org/changeset?old_path=%2Fprint-my-blog%2Ftrunk&old=2075667&new_path=%2Fprint-my-blog%2Ftrunk&new=2075667
wordpress.org/plugins/print-my-blog/#developers
wpvulndb.com/vulnerabilities/9263