diff --git a/libavcodec/sanm.c b/libavcodec/sanm.c
index 8b7c0d9556..abd7981ac6 100644
--- a/libavcodec/sanm.c
+++ b/libavcodec/sanm.c
@@ -974,6 +974,11 @@ static int process_frame_obj(SANMVideoContext *ctx)
     }
     bytestream2_skip(&ctx->gb, 4);
 
+    if (w + FFMAX(left, 0) > ctx->avctx->width || h + FFMAX(top, 0) > ctx->avctx->height) {
+        avpriv_request_sample(ctx->avctx, "overly large frame\n");
+        return AVERROR_PATCHWELCOME;
+    }
+
     switch (codec) {
     case 1:
     case 3: