Unauthorized access in Web Wiz Forum

A vulnerability has found in  Web Wiz Forum (6.34, 7.01, 7.5). Remote user
(authenticated or not) can read message in private forum. Remote user can
post message in private forum.

Software does not compare message to forum, when "quote" mode is used. In
result, remote user (authenticated or not) can read and post message in
private forum, to which he hasn't access. Example:
User "A" has read and write access to Forum1 (FID=1) and no access to Forum2
(FID=2) and message with PID=1111 (in topic TID=11) belong to Forum2(FID=2).
User "A" has no access to topic TID=11 with message PID=1111. However, user
can use "quote" mode for message PID=1111 with Forum1 (FID=1) (instead of
FID=2) to read the private message and answer to it, when use follow URL:

http://webwizforum/post_message_form.asp?mode=quote&PID=1111&FID=1&TID=11&TPN=1
(instead of PID=1111&FID=2&TID=11&TPN=1)

thanks to Tecklord, Pharaoh and other moderator of
http://Forum.SecurityLab.ru


Sorry for my poor English


Solution:

-- begin snip post_message_form.asp ----
'If this is a quoted message read in the message to be quoted
If strMode = "quote" Then

        'Get the number this thread is after
        intTotalNumOfThreads = Request.QueryString("NOP")

        'Get the return thread page
        intRecordPositionPageNum = Request.QueryString("TPN")

---  bug fix by pharaoh ----
       strSQL = "SELECT " & strDbTable & "Topic.Subject FROM " & strDbTable
& "Topic "
        strSQL = strSQL & "WHERE " & strDbTable & "Topic.Forum_ID = " &
CLng(Request.QueryString("FID"))
        strSQL = strSQL & "AND " & strDbTable & "Topic.Topic_ID = " &
CLng(Request.QueryString("TID"))
        rsCommon.Open strSQL, adoCon
        If rsCommon.EOF Then
                rsCommon.Close
                Set rsCommon = Nothing
                Set adoCon = Nothing
                Set adoCon = Nothing
                Response.Redirect "insufficient_permission.asp"
        End If
        rsCommon.Close

        strSQL = "SELECT " & strDbTable & "Author.Author_ID, " & strDbTable
& "Author.Username, " & strDbTable & "Thread.Message "
        strSQL = strSQL & "FROM " & strDbTable & "Thread INNER JOIN " &
strDbTable & "Author ON " & strDbTable & "Thread.Author_ID = " & strDbTable
& "Author.Author_ID "
        strSQL = strSQL & "WHERE " & strDbTable & "Thread.Thread_ID = " &
CLng(Request.QueryString("PID"))
        strSQL = strSQL & "AND " & strDbTable & "Thread.Topic_ID = " &
CLng(Request.QueryString("TID"))

        rsCommon.Open strSQL, adoCon
        If rsCommon.EOF Then
                rsCommon.Close
                Set rsCommon = Nothing
                Set adoCon = Nothing
                Set adoCon = Nothing
                Response.Redirect "insufficient_permission.asp"
        End If
---  bug fix by pharaoh ----
-- end snip post_message_form.asp ----