diff --git a/go.mod b/go.mod
index 14da724f7..f60be046f 100644
--- a/go.mod
+++ b/go.mod
@@ -90,7 +90,7 @@ require (
 	github.com/yosida95/uritemplate/v3 v3.0.2 // indirect
 	golang.org/x/arch v0.24.0 // indirect
 	golang.org/x/crypto v0.48.0 // indirect
-	golang.org/x/net v0.50.0 // indirect
+	golang.org/x/net v0.51.0 // indirect
 	golang.org/x/sync v0.19.0 // indirect
 	golang.org/x/sys v0.41.0 // indirect
 )
diff --git a/go.sum b/go.sum
index e762e45bc..4060997f8 100644
--- a/go.sum
+++ b/go.sum
@@ -271,6 +271,8 @@ golang.org/x/net v0.10.0/go.mod h1:0qNGK6F8kojg2nk9dLZ2mShWaEBan6FAoqfSigmmuDg=
 golang.org/x/net v0.19.0/go.mod h1:CfAk/cbD4CthTvqiEl8NpboMuiuOYsAr/7NOjZJtv1U=
 golang.org/x/net v0.50.0 h1:ucWh9eiCGyDR3vtzso0WMQinm2Dnt8cFMuQa9K33J60=
 golang.org/x/net v0.50.0/go.mod h1:UgoSli3F/pBgdJBHCTc+tp3gmrU4XswgGRgtnwWTfyM=
+golang.org/x/net v0.51.0 h1:94R/GTO7mt3/4wIKpcR5gkGmRLOuE/2hNGeWq/GBIFo=
+golang.org/x/net v0.51.0/go.mod h1:aamm+2QF5ogm02fjy5Bb7CQ0WMt1/WVM7FtyaTLlA9Y=
 golang.org/x/oauth2 v0.23.0/go.mod h1:XYTD2NtWslqkgxebSiOHnXEap4TF09sJSc7H1sXbhtI=
 golang.org/x/oauth2 v0.35.0 h1:Mv2mzuHuZuY2+bkyWXIHMfhNdJAdwW3FuWeCPYN5GVQ=
 golang.org/x/oauth2 v0.35.0/go.mod h1:lzm5WQJQwKZ3nwavOZ3IS5Aulzxi68dUSgRHujetwEA=
diff --git a/pkg/channels/matrix/matrix.go b/pkg/channels/matrix/matrix.go
index 87dd37aa8..7d361bcf8 100644
--- a/pkg/channels/matrix/matrix.go
+++ b/pkg/channels/matrix/matrix.go
@@ -611,7 +611,8 @@ func (c *MatrixChannel) downloadMedia(
 
 	// Encrypted attachments put URL in msgEvt.File and require client-side decryption.
 	if msgEvt != nil && msgEvt.File != nil && msgEvt.URL == "" {
-		if err := msgEvt.File.DecryptInPlace(data); err != nil {
+		err = msgEvt.File.DecryptInPlace(data)
+		if err != nil {
 			return "", fmt.Errorf("decrypt matrix media: %w", err)
 		}
 	}
diff --git a/pkg/channels/matrix/matrix_test.go b/pkg/channels/matrix/matrix_test.go
index af31c671d..6a0ad03b8 100644
--- a/pkg/channels/matrix/matrix_test.go
+++ b/pkg/channels/matrix/matrix_test.go
@@ -18,7 +18,7 @@ func TestMatrixLocalpartMentionRegexp(t *testing.T) {
 	}{
 		{text: "@picoclaw hello", want: true},
 		{text: "hi @picoclaw:matrix.org", want: true},
-		{text: "欢迎一下picoclaw小龙虾", want: false}, // historical false-positive case in PR #356
+		{text: "\u6b22\u8fce\u4e00\u4e0bpicoclaw\u5c0f\u9f99\u867e", want: false}, // historical false-positive case in PR #356
 		{text: "mail test@example.com", want: false},
 	}
 
@@ -87,7 +87,7 @@ func TestIsBotMentioned(t *testing.T) {
 		{
 			name: "localpart without at sign should not match",
 			msg: event.MessageEventContent{
-				Body: "欢迎一下picoclaw小龙虾",
+				Body: "\u6b22\u8fce\u4e00\u4e0bpicoclaw\u5c0f\u9f99\u867e",
 			},
 			want: false,
 		},