diff --git a/include/freerdp/codec/nsc.h b/include/freerdp/codec/nsc.h
index b100ae305..d7b9854ef 100644
--- a/include/freerdp/codec/nsc.h
+++ b/include/freerdp/codec/nsc.h
@@ -84,10 +84,17 @@ extern "C"
 	                                     wStream* WINPR_RESTRICT s,
 	                                     const BYTE* WINPR_RESTRICT bmpdata, UINT32 width,
 	                                     UINT32 height, UINT32 rowstride);
-	FREERDP_API BOOL nsc_decompose_message(NSC_CONTEXT* WINPR_RESTRICT context,
-	                                       wStream* WINPR_RESTRICT s, BYTE* WINPR_RESTRICT bmpdata,
-	                                       UINT32 x, UINT32 y, UINT32 width, UINT32 height,
-	                                       UINT32 rowstride, UINT32 format, UINT32 flip);
+
+#if !defined(WITHOUT_FREERDP_3x_DEPRECATED)
+
+	WINPR_DEPRECATED_VAR(
+	    "[since 3.23.0] deprecated, insecure! missing length checks. use nsc_process_message",
+	    FREERDP_API BOOL nsc_decompose_message(NSC_CONTEXT* WINPR_RESTRICT context,
+	                                           wStream* WINPR_RESTRICT s,
+	                                           BYTE* WINPR_RESTRICT bmpdata, UINT32 x, UINT32 y,
+	                                           UINT32 width, UINT32 height, UINT32 rowstride,
+	                                           UINT32 format, UINT32 flip));
+#endif
 
 	FREERDP_API BOOL nsc_context_reset(NSC_CONTEXT* WINPR_RESTRICT context, UINT32 width,
 	                                   UINT32 height);
diff --git a/libfreerdp/codec/nsc_encode.c b/libfreerdp/codec/nsc_encode.c
index b0fa8f4f2..ec6f282e1 100644
--- a/libfreerdp/codec/nsc_encode.c
+++ b/libfreerdp/codec/nsc_encode.c
@@ -495,6 +495,7 @@ BOOL nsc_compose_message(NSC_CONTEXT* WINPR_RESTRICT context, wStream* WINPR_RES
 	return nsc_write_message(context, s, &message);
 }
 
+#if !defined(WITHOUT_FREERDP_3x_DEPRECATED)
 BOOL nsc_decompose_message(NSC_CONTEXT* WINPR_RESTRICT context, wStream* WINPR_RESTRICT s,
                            BYTE* WINPR_RESTRICT bmpdata, UINT32 x, UINT32 y, UINT32 width,
                            UINT32 height, UINT32 rowstride, UINT32 format, UINT32 flip)
@@ -511,3 +512,4 @@ BOOL nsc_decompose_message(NSC_CONTEXT* WINPR_RESTRICT context, wStream* WINPR_R
 	Stream_Seek(s, size);
 	return TRUE;
 }
+#endif