Small security patch: Make sure that the envelope sender address doesn't

[squirrelmail.git] / functions / smtp.php

diff --git a/functions/smtp.php b/functions/smtp.php
index f8c3fdbbe845a4cacfbc3415e70afa78fa4804bb..ef8684da7d408ad68ac24a13cc6c90658b3b87b2 100644 (file)
--- a/functions/smtp.php
+++ b/functions/smtp.php
@@ -254,8 +254,16 @@
    function sendSendmail($t, $c, $b, $subject, $body, $more_headers) {
       global $sendmail_path, $username, $domain;
 
+      // Build envelope sender address. Make sure it doesn't contain 
+      // spaces or other "weird" chars that would allow a user to
+      // exploit the shell/pipe it is used in.
+      $envelopefrom = "$username@$domain";
+      $envelopefrom = ereg_replace("[[:blank:]]","", $envelopefrom);
+      $envelopefrom = ereg_replace("[[:space:]]","", $envelopefrom);
+      $envelopefrom = ereg_replace("[[:cntrl:]]","", $envelopefrom);
+
       // open pipe to sendmail
-      $fp = popen (escapeshellcmd("$sendmail_path -t -f$username@$domain"), "w");
+      $fp = popen (escapeshellcmd("$sendmail_path -t -f$envelopefrom"), "w");
       
       $headerlength = write822Header ($fp, $t, $c, $b, $subject, $more_headers);
       $bodylength = writeBody($fp, $body);