diff --git a/x/config/config_test.go b/x/config/config_test.go
index 2308c34c..21725596 100644
--- a/x/config/config_test.go
+++ b/x/config/config_test.go
@@ -15,7 +15,6 @@
 package config
 
 import (
-	"encoding/base64"
 	"testing"
 
 	"github.com/stretchr/testify/require"
@@ -55,69 +54,9 @@ func TestSanitizeConfig(t *testing.T) {
 	require.Error(t, err)
 }
 
-func TestShowsocksLagacyBase64URL(t *testing.T) {
-	encoded := base64.URLEncoding.WithPadding(base64.NoPadding).EncodeToString([]byte("aes-256-gcm:1234567@example.com:1234?prefix=HTTP%2F1.1%20"))
-	urls, err := parseConfig("ss://" + string(encoded) + "#outline-123")
-	require.NoError(t, err)
-	require.Equal(t, 1, len(urls))
-	config, err := parseShadowsocksLegacyBase64URL(urls[0])
-	require.Equal(t, "example.com:1234", config.serverAddress)
-	require.Equal(t, "HTTP/1.1 ", string(config.prefix))
-	require.NoError(t, err)
-}
-
-func TestParseShadowsocksURL(t *testing.T) {
-	encoded := base64.URLEncoding.WithPadding(base64.NoPadding).EncodeToString([]byte("aes-256-gcm:1234567@example.com:1234?prefix=HTTP%2F1.1%20"))
-	urls, err := parseConfig("ss://" + string(encoded) + "#outline-123")
-	require.NoError(t, err)
-	require.Equal(t, 1, len(urls))
-	config, err := parseShadowsocksURL(urls[0])
-	require.Equal(t, "example.com:1234", config.serverAddress)
-	require.Equal(t, "HTTP/1.1 ", string(config.prefix))
-	require.NoError(t, err)
-
-	encoded = base64.URLEncoding.WithPadding(base64.NoPadding).EncodeToString([]byte("aes-256-gcm:1234567"))
-	urls, err = parseConfig("ss://" + string(encoded) + "@example.com:1234?prefix=HTTP%2F1.1%20" + "#outline-123")
-	require.NoError(t, err)
-	require.Equal(t, 1, len(urls))
-	config, err = parseShadowsocksURL(urls[0])
-	require.Equal(t, "example.com:1234", config.serverAddress)
-	require.Equal(t, "HTTP/1.1 ", string(config.prefix))
-	require.NoError(t, err)
-}
-
 func TestSocks5URLSanitization(t *testing.T) {
 	configString := "socks5://myuser:mypassword@192.168.1.100:1080"
 	sanitizedConfig, err := SanitizeConfig(configString)
 	require.NoError(t, err)
 	require.Equal(t, "socks5://REDACTED@192.168.1.100:1080", sanitizedConfig)
 }
-
-func TestParseShadowsocksSIP002URLUnsuccessful(t *testing.T) {
-	encoded := base64.URLEncoding.WithPadding(base64.NoPadding).EncodeToString([]byte("aes-256-gcm:1234567@example.com:1234?prefix=HTTP%2F1.1%20"))
-	urls, err := parseConfig("ss://" + string(encoded) + "#outline-123")
-	require.NoError(t, err)
-	require.Equal(t, 1, len(urls))
-	_, err = parseShadowsocksSIP002URL(urls[0])
-	require.Error(t, err)
-}
-
-func TestParseShadowsocksSIP002URLUnsupportedCypher(t *testing.T) {
-	configString := "ss://Y2hhY2hhMjAtaWV0Zi1wb2x5MTMwnTpLeTUyN2duU3FEVFB3R0JpQ1RxUnlT@example.com:1234?prefix=HTTP%2F1.1%20"
-	urls, err := parseConfig(configString)
-	require.NoError(t, err)
-	require.Equal(t, 1, len(urls))
-	_, err = parseShadowsocksSIP002URL(urls[0])
-	require.Error(t, err)
-}
-
-func TestParseShadowsocksSIP002URLSuccessful(t *testing.T) {
-	configString := "ss://Y2hhY2hhMjAtaWV0Zi1wb2x5MTMwNTpLeTUyN2duU3FEVFB3R0JpQ1RxUnlT@example.com:1234?prefix=HTTP%2F1.1%20"
-	urls, err := parseConfig(configString)
-	require.NoError(t, err)
-	require.Equal(t, 1, len(urls))
-	config, err := parseShadowsocksSIP002URL(urls[0])
-	require.NoError(t, err)
-	require.Equal(t, "example.com:1234", config.serverAddress)
-	require.Equal(t, "HTTP/1.1 ", string(config.prefix))
-}
diff --git a/x/config/shadowsocks.go b/x/config/shadowsocks.go
index 33d93229..c65f7ba8 100644
--- a/x/config/shadowsocks.go
+++ b/x/config/shadowsocks.go
@@ -144,11 +144,17 @@ func parseShadowsocksSIP002URL(url *url.URL) (*shadowsocksConfig, error) {
 		return nil, errors.New("host not specified")
 	}
 	config.serverAddress = url.Host
-	cipherInfoBytes, err := base64.URLEncoding.WithPadding(base64.NoPadding).DecodeString(url.User.String())
-	if err != nil {
-		return nil, fmt.Errorf("failed to decode cipher info [%v]: %w", url.User.String(), err)
+	userInfo := url.User.String()
+	// Cipher info can be optionally encoded with Base64URL.
+	encoding := base64.URLEncoding.WithPadding(base64.NoPadding)
+	decodedUserInfo, err := encoding.DecodeString(userInfo)
+	var cipherInfo string
+	if err == nil {
+		cipherInfo = string(decodedUserInfo)
+	} else {
+		cipherInfo = userInfo
 	}
-	cipherName, secret, found := strings.Cut(string(cipherInfoBytes), ":")
+	cipherName, secret, found := strings.Cut(cipherInfo, ":")
 	if !found {
 		return nil, errors.New("invalid cipher info: no ':' separator")
 	}
diff --git a/x/config/shadowsocks_test.go b/x/config/shadowsocks_test.go
index 0fad540b..e9cc50c2 100644
--- a/x/config/shadowsocks_test.go
+++ b/x/config/shadowsocks_test.go
@@ -15,6 +15,7 @@
 package config
 
 import (
+	"encoding/base64"
 	"net/url"
 	"testing"
 
@@ -36,3 +37,87 @@ func Test_sanitizeShadowsocksURL_withPrefix(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, "ss://REDACTED@192.168.100.1:8888?prefix=foo", sanitized)
 }
+
+func TestParseShadowsocksURLFullyEncoded(t *testing.T) {
+	encoded := base64.URLEncoding.WithPadding(base64.NoPadding).EncodeToString([]byte("aes-256-gcm:1234567@example.com:1234?prefix=HTTP%2F1.1%20"))
+	urls, err := parseConfig("ss://" + string(encoded) + "#outline-123")
+	require.NoError(t, err)
+	require.Equal(t, 1, len(urls))
+
+	config, err := parseShadowsocksURL(urls[0])
+
+	require.NoError(t, err)
+	require.Equal(t, "example.com:1234", config.serverAddress)
+	require.Equal(t, "HTTP/1.1 ", string(config.prefix))
+}
+
+func TestParseShadowsocksURLUserInfoEncoded(t *testing.T) {
+	encoded := base64.URLEncoding.WithPadding(base64.NoPadding).EncodeToString([]byte("aes-256-gcm:1234567"))
+	urls, err := parseConfig("ss://" + string(encoded) + "@example.com:1234?prefix=HTTP%2F1.1%20" + "#outline-123")
+	require.NoError(t, err)
+	require.Equal(t, 1, len(urls))
+
+	config, err := parseShadowsocksURL(urls[0])
+
+	require.NoError(t, err)
+	require.Equal(t, "example.com:1234", config.serverAddress)
+	require.Equal(t, "HTTP/1.1 ", string(config.prefix))
+}
+
+func TestParseShadowsocksURLNoEncoding(t *testing.T) {
+	configString := "ss://aes-256-gcm:1234567@example.com:1234"
+	urls, err := parseConfig(configString)
+	require.NoError(t, err)
+	require.Equal(t, 1, len(urls))
+
+	config, err := parseShadowsocksURL(urls[0])
+
+	require.NoError(t, err)
+	require.Equal(t, "example.com:1234", config.serverAddress)
+}
+
+func TestParseShadowsocksURLInvalidCipherInfoFails(t *testing.T) {
+	configString := "ss://aes-256-gcm1234567@example.com:1234"
+	urls, err := parseConfig(configString)
+	require.NoError(t, err)
+	require.Equal(t, 1, len(urls))
+
+	_, err = parseShadowsocksURL(urls[0])
+
+	require.Error(t, err)
+}
+
+func TestParseShadowsocksURLUnsupportedCypherFails(t *testing.T) {
+	configString := "ss://Y2hhY2hhMjAtaWV0Zi1wb2x5MTMwnTpLeTUyN2duU3FEVFB3R0JpQ1RxUnlT@example.com:1234"
+	urls, err := parseConfig(configString)
+	require.NoError(t, err)
+	require.Equal(t, 1, len(urls))
+
+	_, err = parseShadowsocksURL(urls[0])
+
+	require.Error(t, err)
+}
+
+func TestParseShadowsocksLegacyBase64URL(t *testing.T) {
+	encoded := base64.URLEncoding.WithPadding(base64.NoPadding).EncodeToString([]byte("aes-256-gcm:1234567@example.com:1234?prefix=HTTP%2F1.1%20"))
+	urls, err := parseConfig("ss://" + string(encoded) + "#outline-123")
+	require.NoError(t, err)
+	require.Equal(t, 1, len(urls))
+
+	config, err := parseShadowsocksLegacyBase64URL(urls[0])
+
+	require.NoError(t, err)
+	require.Equal(t, "example.com:1234", config.serverAddress)
+	require.Equal(t, "HTTP/1.1 ", string(config.prefix))
+}
+
+func TestParseShadowsocksSIP002URLUnsuccessful(t *testing.T) {
+	encoded := base64.URLEncoding.WithPadding(base64.NoPadding).EncodeToString([]byte("aes-256-gcm:1234567@example.com:1234?prefix=HTTP%2F1.1%20"))
+	urls, err := parseConfig("ss://" + string(encoded) + "#outline-123")
+	require.NoError(t, err)
+	require.Equal(t, 1, len(urls))
+
+	_, err = parseShadowsocksSIP002URL(urls[0])
+
+	require.Error(t, err)
+}