From 27d86def6c8e4859b0615f2be0fd3898611bf073 Mon Sep 17 00:00:00 2001
From: meb <4982406+barrasso@users.noreply.github.com>
Date: Tue, 9 Apr 2024 09:20:55 -0400
Subject: [PATCH] add check for valid synth target

---
 contracts/DynamicSynthRedeemer.sol | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/contracts/DynamicSynthRedeemer.sol b/contracts/DynamicSynthRedeemer.sol
index d4e1cd38e..58d644125 100644
--- a/contracts/DynamicSynthRedeemer.sol
+++ b/contracts/DynamicSynthRedeemer.sol
@@ -80,7 +80,10 @@ contract DynamicSynthRedeemer is Owned, IDynamicSynthRedeemer, MixinResolver {
     }
 
     function _redeem(address synthProxy, uint amountOfSynth) internal {
-        bytes32 currencyKey = ISynth(IProxy(synthProxy).target()).currencyKey();
+        address synthTarget = IProxy(synthProxy).target();
+        require(issuer().synthsByAddress(synthTarget) != bytes32(0), "Invalid synth");
+
+        bytes32 currencyKey = ISynth(synthTarget).currencyKey();
         require(currencyKey != sUSD, "Cannot redeem sUSD");
 
         // Discount rate applied to chainlink price for dynamic redemptions