diff --git a/src/cli/cli.cpp b/src/cli/cli.cpp
index b10a1853b..478ac5c49 100644
--- a/src/cli/cli.cpp
+++ b/src/cli/cli.cpp
@@ -887,6 +887,7 @@ void Interpreter::ProcessDiscover(int argc, char *argv[])
     if (argc > 0)
     {
         SuccessOrExit(error = ParseLong(argv[0], value));
+        VerifyOrExit(value <= static_cast<long>(sizeof(scanChannels) * CHAR_BIT), error = OT_ERROR_INVALID_ARGS);
         scanChannels = 1 << value;
     }
 
@@ -2729,6 +2730,7 @@ void Interpreter::ProcessScan(int argc, char *argv[])
         else
         {
             SuccessOrExit(error = ParseLong(argv[0], value));
+            VerifyOrExit(value < static_cast<long>(sizeof(scanChannels) * CHAR_BIT), error = OT_ERROR_INVALID_ARGS);
             scanChannels = 1 << value;
         }
     }