diff --git a/src/core/serialize.c b/src/core/serialize.c
index 4f7c07a4a..7e3426a59 100644
--- a/src/core/serialize.c
+++ b/src/core/serialize.c
@@ -249,9 +249,16 @@ static int _loadPNGChunkHandler(png_structp png, png_unknown_chunkp chunk) {
 		}
 		const uint8_t* data = chunk->data;
 		data += sizeof(uint32_t) * 2;
-		uncompress((Bytef*) item.data, &len, data, chunk->size);
-		item.size = len;
-		mStateExtdataPut(extdata, tag, &item);
+		if (uncompress((Bytef*) item.data, &len, data, chunk->size) == Z_OK) {
+			if (item.size != len) {
+				mLOG(SAVESTATE, WARN, "Mismatched decompressed extdata %i size (%"PRIz"u vs %"PRIz"u)", tag, item.size, (size_t) len);
+				item.size = len;
+			}
+			mStateExtdataPut(extdata, tag, &item);
+		} else {
+			mLOG(SAVESTATE, WARN, "Failed to decompress extdata chunk");
+			free(item.data);
+		}
 		return 1;
 	}
 	return 0;
@@ -320,7 +327,7 @@ static void* _loadPNGState(struct mCore* core, struct VFile* vf, struct mStateEx
 	return state;
 }
 
-static bool _loadPNGExtadata(struct VFile* vf, struct mStateExtdata* extdata) {
+static bool _loadPNGExtdata(struct VFile* vf, struct mStateExtdata* extdata) {
 	png_structp png = PNGReadOpen(vf, PNG_HEADER_BYTES);
 	png_infop info = png_create_info_struct(png);
 	png_infop end = png_create_info_struct(png);
@@ -511,7 +518,7 @@ void* mCoreExtractState(struct mCore* core, struct VFile* vf, struct mStateExtda
 bool mCoreExtractExtdata(struct mCore* core, struct VFile* vf, struct mStateExtdata* extdata) {
 #ifdef USE_PNG
 	if (isPNG(vf)) {
-		return _loadPNGExtadata(vf, extdata);
+		return _loadPNGExtdata(vf, extdata);
 	}
 #endif
 	if (!core) {