diff -Nuar poppler-0.67.0/utils/pdfdetach.cc poppler-0.67.0-old/utils/pdfdetach.cc
--- poppler-0.67.0/utils/pdfdetach.cc	2021-01-18 15:08:35.960000000 +0800
+++ poppler-0.67.0-old/utils/pdfdetach.cc	2021-01-18 15:29:05.580000000 +0800
@@ -190,14 +190,18 @@
       fileSpec = static_cast<FileSpec *>(embeddedFiles->get(i));
       printf("%d: ", i+1);
       s1 = fileSpec->getFileName();
-      if ((s1->getChar(0) & 0xff) == 0xfe && (s1->getChar(1) & 0xff) == 0xff) {
+      if (!s1) {
+	exitCode = 3;
+	goto err2;
+	}
+      if (s1->hasUnicodeMarker()) {
         isUnicode = gTrue;
         j = 2;
       } else {
         isUnicode = gFalse;
         j = 0;
       }
-      while (j < fileSpec->getFileName()->getLength()) {
+      while (j < s1->getLength()) {
         if (isUnicode) {
           u = ((s1->getChar(j) & 0xff) << 8) | (s1->getChar(j+1) & 0xff);
           j += 2;
@@ -227,14 +231,18 @@
 	p = path;
       }
       s1 = fileSpec->getFileName();
-      if ((s1->getChar(0) & 0xff) == 0xfe && (s1->getChar(1) & 0xff) == 0xff) {
+      if (!s1) {
+	exitCode = 3;
+	goto err2;
+      }
+      if (s1->hasUnicodeMarker()) {
         isUnicode = gTrue;
         j = 2;
       } else {
         isUnicode = gFalse;
         j = 0;
       }
-      while (j < fileSpec->getFileName()->getLength()) {
+      while (j < s1->getLength()) {
         if (isUnicode) {
           u = ((s1->getChar(j) & 0xff) << 8) | (s1->getChar(j+1) & 0xff);
           j += 2;
@@ -275,14 +283,18 @@
     } else {
       p = path;
       s1 = fileSpec->getFileName();
-      if ((s1->getChar(0) & 0xff) == 0xfe && (s1->getChar(1) & 0xff) == 0xff) {
+      if (!s1) {
+	exitCode = 3;
+	goto err2;
+      }
+      if (s1->hasUnicodeMarker()) {
         isUnicode = gTrue;
         j = 2;
       } else {
         isUnicode = gFalse;
         j = 0;
       }
-      while (j < fileSpec->getFileName()->getLength()) {
+      while (j < s1->getLength()) {
         if (isUnicode) {
           u = ((s1->getChar(j) & 0xff) << 8) | (s1->getChar(j+1) & 0xff);
           j += 2;
