diff --git a/context.go b/context.go
index a2e28e5b..911753b8 100644
--- a/context.go
+++ b/context.go
@@ -715,6 +715,24 @@ func (c *Context) MultipartForm() (*multipart.Form, error) {
 	return c.Request.MultipartForm, err
 }
 
+func dirExists(path string) bool {
+	info, err := os.Stat(path)
+	if err != nil {
+		return false
+	}
+	return info.IsDir()
+}
+
+func ensureDirWithMode(dir string, mode fs.FileMode) error {
+	if dirExists(dir) {
+		return nil
+	}
+	if err := os.MkdirAll(dir, mode); err != nil {
+		return err
+	}
+	return os.Chmod(dir, mode)
+}
+
 // SaveUploadedFile uploads the form file to specific dst.
 func (c *Context) SaveUploadedFile(file *multipart.FileHeader, dst string, perm ...fs.FileMode) error {
 	src, err := file.Open()
@@ -728,10 +746,9 @@ func (c *Context) SaveUploadedFile(file *multipart.FileHeader, dst string, perm
 		mode = perm[0]
 	}
 	dir := filepath.Dir(dst)
-	if err = os.MkdirAll(dir, mode); err != nil {
-		return err
-	}
-	if err = os.Chmod(dir, mode); err != nil {
+	// Only chmod newly created directories. Attempting to chmod
+	// pre-existing directories (e.g. /tmp) may fail with EPERM.
+	if err = ensureDirWithMode(dir, mode); err != nil {
 		return err
 	}
 
diff --git a/context_test.go b/context_test.go
index 364a92ae..f523525d 100644
--- a/context_test.go
+++ b/context_test.go
@@ -21,6 +21,7 @@ import (
 	"os"
 	"path/filepath"
 	"reflect"
+	"runtime"
 	"strconv"
 	"strings"
 	"sync"
@@ -248,13 +249,60 @@ func TestSaveUploadedFileWithPermission(t *testing.T) {
 	require.NoError(t, err)
 	assert.Equal(t, "permission_test", f.Filename)
 	var mode fs.FileMode = 0o755
-	require.NoError(t, c.SaveUploadedFile(f, "permission_test", mode))
-	t.Cleanup(func() {
-		assert.NoError(t, os.Remove("permission_test"))
-	})
-	info, err := os.Stat(filepath.Dir("permission_test"))
+	tmpDir := t.TempDir()
+	newSubDir := filepath.Join(tmpDir, "newdir")
+	dst := filepath.Join(newSubDir, "permission_test")
+	require.NoError(t, c.SaveUploadedFile(f, dst, mode))
+	if runtime.GOOS != "windows" {
+		info, err := os.Stat(newSubDir)
+		require.NoError(t, err)
+		assert.Equal(t, mode, info.Mode().Perm())
+	}
+}
+
+func TestDirExists(t *testing.T) {
+	tmpDir := t.TempDir()
+	assert.True(t, dirExists(tmpDir))
+	assert.False(t, dirExists(filepath.Join(tmpDir, "missing")))
+
+	filePath := filepath.Join(tmpDir, "file")
+	require.NoError(t, os.WriteFile(filePath, []byte("test"), 0o600))
+	assert.False(t, dirExists(filePath))
+}
+
+func TestSaveUploadedFileKeepsExistingDirPermission(t *testing.T) {
+	buf := new(bytes.Buffer)
+	mw := multipart.NewWriter(buf)
+	w, err := mw.CreateFormFile("file", "permission_test")
 	require.NoError(t, err)
-	assert.Equal(t, info.Mode().Perm(), mode)
+	_, err = w.Write([]byte("permission_test"))
+	require.NoError(t, err)
+	mw.Close()
+	c, _ := CreateTestContext(httptest.NewRecorder())
+	c.Request, _ = http.NewRequest(http.MethodPost, "/", buf)
+	c.Request.Header.Set("Content-Type", mw.FormDataContentType())
+	f, err := c.FormFile("file")
+	require.NoError(t, err)
+
+	tmpDir := t.TempDir()
+	existingDir := filepath.Join(tmpDir, "existing")
+	require.NoError(t, os.Mkdir(existingDir, 0o700))
+	if runtime.GOOS != "windows" {
+		require.NoError(t, os.Chmod(existingDir, 0o700))
+	}
+
+	var mode fs.FileMode = 0o755
+	dst := filepath.Join(existingDir, "permission_test")
+	require.NoError(t, c.SaveUploadedFile(f, dst, mode))
+
+	saved, err := os.ReadFile(dst)
+	require.NoError(t, err)
+	assert.Equal(t, "permission_test", string(saved))
+	if runtime.GOOS != "windows" {
+		info, err := os.Stat(existingDir)
+		require.NoError(t, err)
+		assert.Equal(t, fs.FileMode(0o700), info.Mode().Perm())
+	}
 }
 
 func TestSaveUploadedFileWithPermissionFailed(t *testing.T) {
diff --git a/go.mod b/go.mod
index df181253..c67c5fed 100644
--- a/go.mod
+++ b/go.mod
@@ -12,7 +12,7 @@ require (
 	github.com/mattn/go-isatty v0.0.20
 	github.com/modern-go/reflect2 v1.0.2
 	github.com/pelletier/go-toml/v2 v2.2.4
-	github.com/quic-go/quic-go v0.59.0
+	github.com/quic-go/quic-go v0.59.1
 	github.com/stretchr/testify v1.11.1
 	github.com/ugorji/go/codec v1.3.1
 	go.mongodb.org/mongo-driver/v2 v2.5.0
diff --git a/go.sum b/go.sum
index f7f9e27b..e69bfeee 100644
--- a/go.sum
+++ b/go.sum
@@ -52,8 +52,8 @@ github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZb
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/quic-go/qpack v0.6.0 h1:g7W+BMYynC1LbYLSqRt8PBg5Tgwxn214ZZR34VIOjz8=
 github.com/quic-go/qpack v0.6.0/go.mod h1:lUpLKChi8njB4ty2bFLX2x4gzDqXwUpaO1DP9qMDZII=
-github.com/quic-go/quic-go v0.59.0 h1:OLJkp1Mlm/aS7dpKgTc6cnpynnD2Xg7C1pwL6vy/SAw=
-github.com/quic-go/quic-go v0.59.0/go.mod h1:upnsH4Ju1YkqpLXC305eW3yDZ4NfnNbmQRCMWS58IKU=
+github.com/quic-go/quic-go v0.59.1 h1:0Gmua0HW1Tv7ANR7hUYwRyD0MG5OJfgvYSZasGZzBic=
+github.com/quic-go/quic-go v0.59.1/go.mod h1:upnsH4Ju1YkqpLXC305eW3yDZ4NfnNbmQRCMWS58IKU=
 github.com/rogpeppe/go-internal v1.10.0 h1:TMyTOH3F/DB16zRVcYyreMH6GnZZrwQVAoYjRBZyWFQ=
 github.com/rogpeppe/go-internal v1.10.0/go.mod h1:UQnix2H7Ngw/k4C5ijL5+65zddjncjaFoBhdsK/akog=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=