diff --git a/poppler/JPEG2000Stream.cc b/poppler/JPEG2000Stream.cc
--- a/poppler/JPEG2000Stream.cc
+++ b/poppler/JPEG2000Stream.cc
@@ -201,7 +201,7 @@ void JPXStream::init()
   if (getDict()) smaskInData = getDict()->lookup("SMaskInData");
 
   int bufSize = BUFFER_INITIAL_SIZE;
-  if (oLen.isInt()) bufSize = oLen.getInt();
+  if (oLen.isInt() && oLen.getInt() > 0) bufSize = oLen.getInt();
 
   if (cspace.isArray() && cspace.arrayGetLength() > 0) {

@@ -365,7 +365,7 @@ void JPXStream::init()
   }
 
   int bufSize = BUFFER_INITIAL_SIZE;
-  if (oLen.isInt()) bufSize = oLen.getInt();
+  if (oLen.isInt() && oLen.getInt() > 0) bufSize = oLen.getInt();
 
   if (cspace.isArray() && cspace.arrayGetLength() > 0) {