diff --git a/staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/fuzzer/fuzzer.go b/staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/fuzzer/fuzzer.go
index 18a33291368..fcde569686c 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/fuzzer/fuzzer.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/fuzzer/fuzzer.go
@@ -58,8 +58,24 @@ func Funcs(codecs runtimeserializer.CodecFactory) []interface{} {
 					case reflect.Interface, reflect.Map, reflect.Slice, reflect.Ptr:
 						isValue = false
 					}
-					if isValue || c.Intn(5) == 0 {
+					if isValue || c.Intn(10) == 0 {
 						c.Fuzz(vobj.Field(i).Addr().Interface())
+
+						// JSON keys must not contain escape char with our JSON codec (jsoniter)
+						// TODO: remove this when/if we moved from jsoniter.ConfigFastest to ConfigCompatibleWithStandardLibrary
+						if field.Type.Kind() == reflect.Map {
+							keys := append([]reflect.Value(nil), vobj.Field(i).MapKeys()...)
+							for _, k := range keys {
+								stripped := toJSONString(k.String())
+								if stripped == k.String() {
+									continue
+								}
+								// set new key
+								vobj.Field(i).SetMapIndex(reflect.ValueOf(stripped), vobj.Field(i).MapIndex(k))
+								// remove old
+								vobj.Field(i).SetMapIndex(k, reflect.Value{})
+							}
+						}
 					}
 				}
 			}
@@ -109,3 +125,13 @@ func Funcs(codecs runtimeserializer.CodecFactory) []interface{} {
 		},
 	}
 }
+
+func toJSONString(s string) string {
+	return strings.Map(func(r rune) rune {
+		// replace chars which are not supported in keys by jsoniter.ConfigFastest
+		if r == '\\' || r == '"' {
+			return 'x'
+		}
+		return r
+	}, s)
+}