diff --git a/internal/utils/common_files.go b/internal/utils/common_files.go
new file mode 100644
index 0000000..6fc2dc2
--- /dev/null
+++ b/internal/utils/common_files.go
@@ -0,0 +1,38 @@
+// Copyright 2024 GoEdge CDN goedge.cdn@gmail.com. All rights reserved. Official site: https://goedge.cn .
+
+package utils
+
+import (
+	"github.com/TeaOSLab/EdgeNode/internal/zero"
+	"strings"
+)
+
+var commonFileExtensionsMap = map[string]zero.Zero{
+	".ico":   zero.New(),
+	".jpg":   zero.New(),
+	".jpeg":  zero.New(),
+	".gif":   zero.New(),
+	".png":   zero.New(),
+	".webp":  zero.New(),
+	".woff2": zero.New(),
+	".js":    zero.New(),
+	".css":   zero.New(),
+	".ttf":   zero.New(),
+	".otf":   zero.New(),
+	".fnt":   zero.New(),
+	".svg":   zero.New(),
+	".map":   zero.New(),
+}
+
+// IsCommonFileExtension 判断是否为常用文件扩展名
+// 不区分大小写，且不限于是否加点符号（.）
+func IsCommonFileExtension(ext string) bool {
+	if len(ext) == 0 {
+		return false
+	}
+	if ext[0] != '.' {
+		ext = "." + ext
+	}
+	_, ok := commonFileExtensionsMap[strings.ToLower(ext)]
+	return ok
+}
diff --git a/internal/utils/common_files_test.go b/internal/utils/common_files_test.go
new file mode 100644
index 0000000..7f019f6
--- /dev/null
+++ b/internal/utils/common_files_test.go
@@ -0,0 +1,20 @@
+// Copyright 2024 GoEdge CDN goedge.cdn@gmail.com. All rights reserved. Official site: https://goedge.cn .
+
+package utils_test
+
+import (
+	"github.com/TeaOSLab/EdgeNode/internal/utils"
+	"github.com/iwind/TeaGo/assert"
+	"testing"
+)
+
+func TestIsCommonFileExtension(t *testing.T) {
+	var a = assert.NewAssertion(t)
+
+	a.IsTrue(utils.IsCommonFileExtension(".jpg"))
+	a.IsTrue(utils.IsCommonFileExtension("png"))
+	a.IsTrue(utils.IsCommonFileExtension("PNG"))
+	a.IsTrue(utils.IsCommonFileExtension(".PNG"))
+	a.IsTrue(utils.IsCommonFileExtension("Png"))
+	a.IsFalse(utils.IsCommonFileExtension("zip"))
+}
diff --git a/internal/waf/checkpoints/cc2.go b/internal/waf/checkpoints/cc2.go
index 03857b3..d1abd58 100644
--- a/internal/waf/checkpoints/cc2.go
+++ b/internal/waf/checkpoints/cc2.go
@@ -4,32 +4,16 @@ package checkpoints
 
 import (
 	"fmt"
+	"github.com/TeaOSLab/EdgeNode/internal/utils"
 	"github.com/TeaOSLab/EdgeNode/internal/utils/counters"
 	"github.com/TeaOSLab/EdgeNode/internal/waf/requests"
-	"github.com/TeaOSLab/EdgeNode/internal/waf/utils"
-	"github.com/TeaOSLab/EdgeNode/internal/zero"
+	wafutils "github.com/TeaOSLab/EdgeNode/internal/waf/utils"
 	"github.com/iwind/TeaGo/maps"
 	"github.com/iwind/TeaGo/types"
 	"path/filepath"
 	"strings"
 )
 
-var commonFileExtensionsMap = map[string]zero.Zero{
-	".ico":   zero.New(),
-	".jpg":   zero.New(),
-	".jpeg":  zero.New(),
-	".gif":   zero.New(),
-	".png":   zero.New(),
-	".webp":  zero.New(),
-	".woff2": zero.New(),
-	".js":    zero.New(),
-	".css":   zero.New(),
-	".ttf":   zero.New(),
-	".otf":   zero.New(),
-	".fnt":   zero.New(),
-	".svg":   zero.New(),
-}
-
 // CC2Checkpoint 新的CC
 type CC2Checkpoint struct {
 	Checkpoint
@@ -61,16 +45,12 @@ func (this *CC2Checkpoint) RequestValue(req requests.Request, param string, opti
 		threshold = 1000
 	}**/
 
-	var ignoreCommonFiles = options.GetBool("ignoreCommonFiles")
-	if ignoreCommonFiles {
+	if options.GetBool("ignoreCommonFiles") {
 		var rawReq = req.WAFRaw()
 		if len(rawReq.Referer()) > 0 {
 			var ext = filepath.Ext(rawReq.URL.Path)
-			if len(ext) > 0 {
-				_, ok := commonFileExtensionsMap[strings.ToLower(ext)]
-				if ok {
-					return
-				}
+			if len(ext) > 0 && utils.IsCommonFileExtension(ext) {
+				return
 			}
 		}
 	}
@@ -114,6 +94,6 @@ func (this *CC2Checkpoint) ResponseValue(req requests.Request, resp *requests.Re
 	return
 }
 
-func (this *CC2Checkpoint) CacheLife() utils.CacheLife {
-	return utils.CacheDisabled
+func (this *CC2Checkpoint) CacheLife() wafutils.CacheLife {
+	return wafutils.CacheDisabled
 }