diff --git a/lib/redmine/thumbnail.rb b/lib/redmine/thumbnail.rb
index 2f9b41ce8..611c36703 100644
--- a/lib/redmine/thumbnail.rb
+++ b/lib/redmine/thumbnail.rb
@@ -24,6 +24,7 @@ module Redmine
     extend Redmine::Utils::Shell
 
     CONVERT_BIN = (Redmine::Configuration['imagemagick_convert_command'] || 'convert').freeze
+    CONVERT_TIMEOUT = 10
     GS_BIN = (
       Redmine::Configuration['gs_command'] ||
       ('gswin64c' if Redmine::Platform.mswin?) ||
@@ -47,9 +48,9 @@ module Redmine
         size_option = "#{size}x#{size}>"
 
         if is_pdf
-          cmd = "#{shell_quote CONVERT_BIN} #{shell_quote "#{source}[0]"} -thumbnail #{shell_quote size_option} #{shell_quote "png:#{target}"}"
+          cmd = "#{shell_quote CONVERT_BIN} -limit time #{shell_quote CONVERT_TIMEOUT.to_s} #{shell_quote "#{source}[0]"} -thumbnail #{shell_quote size_option} #{shell_quote "png:#{target}"}"
         else
-          cmd = "#{shell_quote CONVERT_BIN} #{shell_quote source} -auto-orient -thumbnail #{shell_quote size_option} #{shell_quote target}"
+          cmd = "#{shell_quote CONVERT_BIN}  -limit time #{shell_quote CONVERT_TIMEOUT.to_s} #{shell_quote source} -auto-orient -thumbnail #{shell_quote size_option} #{shell_quote target}"
         end
         unless system(cmd)
           logger.error("Creating thumbnail failed (#{$?}):\nCommand: #{cmd}")