diff --git a/de4dot.code/deobfuscators/CliSecure/CliSecureRtType.cs b/de4dot.code/deobfuscators/CliSecure/CliSecureRtType.cs
index 8ac2b8b2..8e36c7fc 100644
--- a/de4dot.code/deobfuscators/CliSecure/CliSecureRtType.cs
+++ b/de4dot.code/deobfuscators/CliSecure/CliSecureRtType.cs
@@ -202,5 +202,35 @@ namespace de4dot.code.deobfuscators.CliSecure {
 		public bool isAtLeastVersion50() {
 			return DotNetUtils.hasPinvokeMethod(cliSecureRtType, "LoadLibraryA");
 		}
+
+		public void findStringDecrypterMethod() {
+			if (cliSecureRtType != null)
+				return;
+
+			foreach (var type in module.Types) {
+				if (type.Fields.Count != 0)
+					continue;
+				if (type.Methods.Count != 1)
+					continue;
+				var cs = type.Methods[0];
+				if (!isOldStringDecrypterMethod(cs))
+					continue;
+
+				cliSecureRtType = type;
+				stringDecrypterMethod = cs;
+				return;
+			}
+		}
+
+		static bool isOldStringDecrypterMethod(MethodDefinition method) {
+			if (method == null || method.Body == null || !method.IsStatic)
+				return false;
+			if (!DotNetUtils.isMethod(method, "System.String", "(System.String)"))
+				return false;
+			if (!DeobUtils.hasInteger(method, 0xFF))
+				return false;
+
+			return true;
+		}
 	}
 }
diff --git a/de4dot.code/deobfuscators/CliSecure/Deobfuscator.cs b/de4dot.code/deobfuscators/CliSecure/Deobfuscator.cs
index 07790541..db4bc5d9 100644
--- a/de4dot.code/deobfuscators/CliSecure/Deobfuscator.cs
+++ b/de4dot.code/deobfuscators/CliSecure/Deobfuscator.cs
@@ -214,6 +214,9 @@ namespace de4dot.code.deobfuscators.CliSecure {
 		public override void deobfuscateBegin() {
 			base.deobfuscateBegin();
 
+			cliSecureRtType.findStringDecrypterMethod();
+			stringDecrypter.Method = cliSecureRtType.StringDecrypterMethod;
+
 			addAttributesToBeRemoved(cliSecureAttributes, "Obfuscator attribute");
 
 			if (options.DecryptResources) {
diff --git a/de4dot.code/deobfuscators/CliSecure/StringDecrypter.cs b/de4dot.code/deobfuscators/CliSecure/StringDecrypter.cs
index e59481e6..ef3e5e5c 100644
--- a/de4dot.code/deobfuscators/CliSecure/StringDecrypter.cs
+++ b/de4dot.code/deobfuscators/CliSecure/StringDecrypter.cs
@@ -38,6 +38,7 @@ namespace de4dot.code.deobfuscators.CliSecure {
 
 		public MethodDefinition Method {
 			get { return stringDecrypterMethod; }
+			set { stringDecrypterMethod = value; }
 		}
 
 		public StringDecrypter(ModuleDefinition module, MethodDefinition stringDecrypterMethod) {