diff --git a/3rdparty/libspng/CMakeLists.txt b/3rdparty/libspng/CMakeLists.txt
index afd6d5fe4069..ab0a41a5c619 100644
--- a/3rdparty/libspng/CMakeLists.txt
+++ b/3rdparty/libspng/CMakeLists.txt
@@ -23,7 +23,6 @@ if(MSVC)
 endif(MSVC)
 
 add_library(${SPNG_LIBRARY} STATIC ${OPENCV_3RDPARTY_EXCLUDE_FROM_ALL} ${spng_headers} ${spng_sources})
-ocv_warnings_disable(CMAKE_C_FLAGS -Wunused-variable)
 target_link_libraries(${SPNG_LIBRARY} ${ZLIB_LIBRARIES})
 
 set_target_properties(${SPNG_LIBRARY}
diff --git a/3rdparty/libspng/LICENSE b/3rdparty/libspng/LICENSE
index f96574b80d2a..a29d5a2fa8d4 100644
--- a/3rdparty/libspng/LICENSE
+++ b/3rdparty/libspng/LICENSE
@@ -1,6 +1,6 @@
 BSD 2-Clause License
 
-Copyright (c) 2018-2022, Randy <randy408@protonmail.com>
+Copyright (c) 2018-2023, Randy <randy408@protonmail.com>
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
diff --git a/3rdparty/libspng/spng.c b/3rdparty/libspng/spng.c
index 6ed60f2d6ce6..b22b7110a17b 100644
--- a/3rdparty/libspng/spng.c
+++ b/3rdparty/libspng/spng.c
@@ -2691,6 +2691,7 @@ static int read_non_idat_chunks(spng_ctx *ctx)
             if(!memcmp(chunk.type, type_exif, 4))
             {
                 if(ctx->file.exif) return SPNG_EDUP_EXIF;
+                if(!chunk.length) return SPNG_EEXIF;
 
                 ctx->file.exif = 1;
 
@@ -4999,11 +5000,11 @@ void spng_ctx_free(spng_ctx *ctx)
     spng__free(ctx, ctx->prev_scanline_buf);
     spng__free(ctx, ctx->filtered_scanline_buf);
 
-    spng_free_fn *free_func = ctx->alloc.free_fn;
+    spng_free_fn *free_fn = ctx->alloc.free_fn;
 
     memset(ctx, 0, sizeof(spng_ctx));
 
-    free_func(ctx);
+    free_fn(ctx);
 }
 
 static int buffer_read_fn(spng_ctx *ctx, void *user, void *data, size_t n)
@@ -5743,7 +5744,8 @@ int spng_set_iccp(spng_ctx *ctx, struct spng_iccp *iccp)
     SPNG_SET_CHUNK_BOILERPLATE(iccp);
 
     if(check_png_keyword(iccp->profile_name)) return SPNG_EICCP_NAME;
-    if(!iccp->profile_len || iccp->profile_len > UINT_MAX) return 1;
+    if(!iccp->profile_len) return SPNG_ECHUNK_SIZE;
+    if(iccp->profile_len > spng_u32max) return SPNG_ECHUNK_STDLEN;
 
     if(ctx->iccp.profile && !ctx->user.iccp) spng__free(ctx, ctx->iccp.profile);
 
diff --git a/3rdparty/libspng/spng.h b/3rdparty/libspng/spng.h
index 5937d6c15de3..8f946337bfa2 100644
--- a/3rdparty/libspng/spng.h
+++ b/3rdparty/libspng/spng.h
@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: (BSD-2-Clause AND libpng-2.0) */
+/* SPDX-License-Identifier: BSD-2-Clause */
 #ifndef SPNG_H
 #define SPNG_H
 
@@ -28,7 +28,7 @@ extern "C" {
 
 #define SPNG_VERSION_MAJOR 0
 #define SPNG_VERSION_MINOR 7
-#define SPNG_VERSION_PATCH 3
+#define SPNG_VERSION_PATCH 4
 
 enum spng_errno
 {