author.: l0om product: guestbox (latest non-BETA) 0.6 page: dork: "Login - Guestbox 0.6" inurl:guestbox.php someone asked me to check the guestbook named "guestbox" and thats the advisory based on my checks. 1.0 everyone can set admin comments to all entries -------------------------------------------------- in case of setting an admin comment to some gb entry you normaly have to log in as admin. as you can see in the sources down you dont need to be logged in as admin to set an admin comment because the programmer missed it to check the "$admin" value at this point of the switch case. simply create the following html document and post comments as admin:

---8<--- source:action.php ---8<--- [...] INCLUDE "gb_config.php"; INCLUDE "gb_functions.php"; switch ($_GET['action']) { case "comment" : if (isset($_POST['submit'])) { // // admin check???? // edit_entry($gbdaten, $_GET['nummer'], trim(get_entry($gbdaten, $_GET['nummer'])).preg_replace("/(\015\012)|(\015)|(\012)/","
",html entities($_POST['text']))); [...] // like this if ($admin == 1) { [...] "; [...] if ($admin == 1) { $datei=fopen("./".$gbdaten,"r"); while(feof($datei)==0) { [...] 2.0 XSS/HTML injection -------- if you add an entry to the guestbook you can inject javascript code. there have to be "magic_quotes_gpc" set to "Off" in your php.ini for injection as it will otherwise qoute out all your GET/POST data... the sources says: gbshow.php: if (preg_match("/http:\/\/.+/i", $data[3])) { $homepage=".$data[3]."; [...] what can be exploited with the following string in the "hompage" field.: http://"> btw: there are a few other ways to inject code to the gb. if "magic_quotes_pgc" is set to "On" you still can INJECT HTML of course. 3.0 view IPs ------------ for normal its an admin feature to view the ip address of the host which have added the entry to the guestbook. simply view the guestbook with all data for all entrys with opening the "/gb/gblog" does the trick for everyone as well. have phun, l0om