diff --git a/NEWS b/NEWS
index c48608fb..8690324f 100644
--- a/NEWS
+++ b/NEWS
@@ -27,8 +27,9 @@ NEWS ( CHANGELOG and HISTORY )                                     HTMLPurifier
 - Spurious internal content reorganization error suppressed
 - HTMLDefinition->addElement now returns a reference to the created
   element object, as implied by the documentation
-- Phorum mod's HTML Purifier help message expanded, however, a new tarball
-  was not released
+- Phorum mod's HTML Purifier help message expanded (unreleased elsewhere)
+- Fix a theoretical class of infinite loops from DirectLex reported
+  by Nate Abele
 . %Core.AcceptFullDocuments renamed to %Core.ConvertDocumentToFragment 
   to better communicate its purpose
 . Error unit tests can now specify the expectation of no errors. Future
diff --git a/library/HTMLPurifier/Lexer/DirectLex.php b/library/HTMLPurifier/Lexer/DirectLex.php
index b3639916..86c0a211 100644
--- a/library/HTMLPurifier/Lexer/DirectLex.php
+++ b/library/HTMLPurifier/Lexer/DirectLex.php
@@ -160,9 +160,15 @@ class HTMLPurifier_Lexer_DirectLex extends HTMLPurifier_Lexer
                 
                 $segment = substr($html, $cursor, $strlen_segment);
                 
+                if ($segment === false) {
+                    // somehow, we attempted to access beyond the end of
+                    // the string, defense-in-depth, reported by Nate Abele
+                    break;
+                }
+                
                 // Check if it's a comment
                 if (
-                    substr($segment, 0, 3) == '!--'
+                    substr($segment, 0, 3) === '!--'
                 ) {
                     // re-determine segment length, looking for -->
                     $position_comment_end = strpos($html, '-->', $cursor);
@@ -237,7 +243,7 @@ class HTMLPurifier_Lexer_DirectLex extends HTMLPurifier_Lexer
                 // trailing slash. Remember, we could have a tag like <br>, so
                 // any later token processing scripts must convert improperly
                 // classified EmptyTags from StartTags.
-                $is_self_closing= (strrpos($segment,'/') === $strlen_segment-1);
+                $is_self_closing = (strrpos($segment,'/') === $strlen_segment-1);
                 if ($is_self_closing) {
                     $strlen_segment--;
                     $segment = substr($segment, 0, $strlen_segment);