From 43d92bf855155e8e716ecbb50ed94c2ed41ff9f6 Mon Sep 17 00:00:00 2001
From: Dirk Lemstra <dirk@lemstra.org>
Date: Thu, 14 Aug 2025 21:21:59 +0200
Subject: [PATCH] Added checks for invalid with or height to ThumbnailImage
 (https://github.com/ImageMagick/ImageMagick/security/advisories/GHSA-fh55-q5pj-pxgw)

---
 MagickCore/resize.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/MagickCore/resize.c b/MagickCore/resize.c
index d1744ea365..0a0c60aabe 100644
--- a/MagickCore/resize.c
+++ b/MagickCore/resize.c
@@ -4613,6 +4613,8 @@ MagickExport Image *ThumbnailImage(const Image *image,const size_t columns,
   assert(exception->signature == MagickCoreSignature);
   if (IsEventLogging() != MagickFalse)
     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
+  if ((columns == 0) || (rows == 0))
+    ThrowImageException(ImageError,"NegativeOrZeroImageSize");
   thumbnail_image=CloneImage(image,0,0,MagickTrue,exception);
   if (thumbnail_image == (Image *) NULL)
     return(thumbnail_image);