diff --git a/docs/NEWS b/docs/NEWS
index ecf052459..be3cc2a59 100644
--- a/docs/NEWS
+++ b/docs/NEWS
@@ -1,6 +1,8 @@
 Version 2.3.5-beta1 ()
 ------------------------------------------------------------------------
 
+   * Fix: Truncate extension of media items to 5 chars (which ist the
+          max length of the corresponding database field).
 
 Version 2.3.4 (March 25th, 2020)
 ------------------------------------------------------------------------
diff --git a/include/functions_images.inc.php b/include/functions_images.inc.php
index 006ca698c..8b59552fb 100644
--- a/include/functions_images.inc.php
+++ b/include/functions_images.inc.php
@@ -2040,6 +2040,13 @@ function serendipity_uploadSecure($var, $strip_paths = true, $append_slash = fal
         }
     }
 
+    # truncate extensions to 5 chars
+    # 1) (\.[^.]{0,5}+) five chars after a dot are captured (possessively)
+    # 2) expression matches only if followed by anything that is no dot
+    #    and has no / or \ at the end
+    # 3) if epxression matches, everything after the capture group is deleted
+    $var = preg_replace('@(\.[^.]{0,5}+)[^./\\\]*[^/\\\]{1,1}?$@', '$1', $var);
+
     return $var;
 }