-

OskarStark · OskarStark · commit ed51a41453df · 2023-10-13T12:51:13.000+02:00
diff --git a/src/Symfony/Component/HttpFoundation/HeaderUtils.php b/src/Symfony/Component/HttpFoundation/HeaderUtils.php
@@ -261,7 +261,7 @@ private static function groupParts(array $matches, string $separators, bool $fir
             if (!$first && $previousMatchWasSeparator && isset($match['separator']) && $match['separator'] === $separator) {
                 $previousMatchWasSeparator = true;
                 $partMatches[$i][] = $match;
-            } elseif (!$first && !isset($match['separator']) && isset($matches[$key + 1], $matches[$key + 1]['separator']) && $matches[$key+1]['separator'] === $separator && !isset($matches[$key+2])) { // ends with a separator, so it must be part of the value
+            } elseif (!$first && !isset($match['separator']) && ($matches[$key + 1]['separator'] ?? null) === $separator && !isset($matches[$key + 2])) { // ends with a separator, so it must be part of the value
                 $numberOfSeparators = 0;
                 for ($i = $key+1; $i < \count($matches); ++$i) {
                     if (!array_key_exists('separator', $matches[$i])) {
