CVE-2018-5704: Prevent some forms of Cross Protocol Scripting attacks

[openocd.git] / src / server / startup.tcl

diff --git a/src/server/startup.tcl b/src/server/startup.tcl
index 677bb2de74d2fab64b6f49d58620c8e8a4a11d46..dd1b31e417dd15942a3906dbf3b25a5734aa062e 100644 (file)
--- a/src/server/startup.tcl
+++ b/src/server/startup.tcl
@@ -1,4 +1,6 @@
-# Handle GDB 'R' packet. Can be overriden by configuration script,
+# Defines basic Tcl procs for OpenOCD server modules
+
+# Handle GDB 'R' packet. Can be overridden by configuration script,
 # but it's not something one would expect target scripts to do
 # normally
 proc ocd_gdb_restart {target_id} {
@@ -6,3 +8,14 @@ proc ocd_gdb_restart {target_id} {
        # one target
        reset halt
 }
+
+proc prevent_cps {} {
+       echo "Possible SECURITY ATTACK detected."
+       echo "It looks like somebody is sending POST or Host: commands to OpenOCD."
+       echo "This is likely due to an attacker attempting to use Cross Protocol Scripting"
+       echo "to compromise your OpenOCD instance. Connection aborted."
+       exit
+}
+
+proc POST {args} { prevent_cps }
+proc Host: {args} { prevent_cps }