diff --git a/Sources/SwiftUI/ImageBinder.swift b/Sources/SwiftUI/ImageBinder.swift
index 124c4ca84..cc0d4b8fc 100644
--- a/Sources/SwiftUI/ImageBinder.swift
+++ b/Sources/SwiftUI/ImageBinder.swift
@@ -149,13 +149,13 @@ extension KFImage {
         /// Restores the download task priority to default if it is in progress.
         func restorePriorityOnAppear() {
             guard let downloadTask = downloadTask, loading == true else { return }
-            downloadTask.sessionTask.task.priority = URLSessionTask.defaultPriority
+            downloadTask.sessionTask?.task.priority = URLSessionTask.defaultPriority
         }
         
         /// Reduce the download task priority if it is in progress.
         func reducePriorityOnDisappear() {
             guard let downloadTask = downloadTask, loading == true else { return }
-            downloadTask.sessionTask.task.priority = URLSessionTask.lowPriority
+            downloadTask.sessionTask?.task.priority = URLSessionTask.lowPriority
         }
     }
 }
diff --git a/Sources/Utility/String+SHA256.swift b/Sources/Utility/String+SHA256.swift
index 8898df1de..65738d659 100644
--- a/Sources/Utility/String+SHA256.swift
+++ b/Sources/Utility/String+SHA256.swift
@@ -45,14 +45,15 @@ extension KingfisherWrapper where Base == String {
     }
 
     var ext: String? {
-        var ext = ""
-        if let index = base.lastIndex(of: ".") {
-            let extRange = base.index(index, offsetBy: 1)..<base.endIndex
-            ext = String(base[extRange])
-        }
-        guard let firstSeg = ext.split(separator: "@").first else {
+        guard let firstSeg = base.split(separator: "@").first else {
             return nil
         }
-        return firstSeg.count > 0 ? String(firstSeg) : nil
+
+        var ext = ""
+        if let index = firstSeg.lastIndex(of: ".") {
+            let extRange = firstSeg.index(index, offsetBy: 1)..<firstSeg.endIndex
+            ext = String(firstSeg[extRange])
+        }
+        return ext.count > 0 ? ext : nil
     }
 }