diff --git a/lib/tzinfo.rb b/lib/tzinfo.rb
index 96e94ade..abac4419 100644
--- a/lib/tzinfo.rb
+++ b/lib/tzinfo.rb
@@ -7,6 +7,8 @@ module TZInfo
 
 require_relative 'tzinfo/version'
 
+require_relative 'tzinfo/untaint_ext' if RUBY_VERSION >= '2.7'
+
 require_relative 'tzinfo/string_deduper'
 
 require_relative 'tzinfo/timestamp'
diff --git a/lib/tzinfo/data_sources/ruby_data_source.rb b/lib/tzinfo/data_sources/ruby_data_source.rb
index f99fafde..bc608e84 100644
--- a/lib/tzinfo/data_sources/ruby_data_source.rb
+++ b/lib/tzinfo/data_sources/ruby_data_source.rb
@@ -2,6 +2,8 @@
 # frozen_string_literal: true
 
 module TZInfo
+  using UntaintExt if TZInfo.const_defined?(:UntaintExt)
+
   module DataSources
     # A {TZInfoDataNotFound} exception is raised if the tzinfo-data gem could
     # not be found (i.e. `require 'tzinfo/data'` failed) when selecting the Ruby
diff --git a/lib/tzinfo/data_sources/zoneinfo_data_source.rb b/lib/tzinfo/data_sources/zoneinfo_data_source.rb
index d23328c6..ea58d203 100644
--- a/lib/tzinfo/data_sources/zoneinfo_data_source.rb
+++ b/lib/tzinfo/data_sources/zoneinfo_data_source.rb
@@ -2,6 +2,8 @@
 # frozen_string_literal: true
 
 module TZInfo
+  using UntaintExt if TZInfo.const_defined?(:UntaintExt)
+
   module DataSources
     # An {InvalidZoneinfoDirectory} exception is raised if {ZoneinfoDataSource}
     # is initialized with a specific zoneinfo path that is not a valid zoneinfo
diff --git a/lib/tzinfo/data_sources/zoneinfo_reader.rb b/lib/tzinfo/data_sources/zoneinfo_reader.rb
index f9e3906a..b74d162a 100644
--- a/lib/tzinfo/data_sources/zoneinfo_reader.rb
+++ b/lib/tzinfo/data_sources/zoneinfo_reader.rb
@@ -2,6 +2,8 @@
 # frozen_string_literal: true
 
 module TZInfo
+  using UntaintExt if TZInfo.const_defined?(:UntaintExt)
+
   module DataSources
     # An {InvalidZoneinfoFile} exception is raised if an attempt is made to load
     # an invalid zoneinfo file.
diff --git a/lib/tzinfo/untaint_ext.rb b/lib/tzinfo/untaint_ext.rb
new file mode 100644
index 00000000..ace0f37f
--- /dev/null
+++ b/lib/tzinfo/untaint_ext.rb
@@ -0,0 +1,18 @@
+# encoding: UTF-8
+# frozen_string_literal: true
+
+module TZInfo
+  # Object#untaint is deprecated in Ruby >= 2.7 and will be removed in 3.0.
+  # UntaintExt adds a refinement to make Object#untaint a no-op and avoid the
+  # warning.
+  #
+  # @private
+  module UntaintExt # :nodoc:
+    refine Object do
+      def untaint
+        self
+      end
+    end
+  end
+  private_constant :UntaintExt
+end
diff --git a/test/data_sources/tc_ruby_data_source.rb b/test/data_sources/tc_ruby_data_source.rb
index 89851c6a..21259a48 100644
--- a/test/data_sources/tc_ruby_data_source.rb
+++ b/test/data_sources/tc_ruby_data_source.rb
@@ -3,6 +3,8 @@
 
 require_relative '../test_utils'
 
+using TestUtils::TaintExt if TestUtils.const_defined?(:TaintExt)
+
 include TZInfo
 
 module DataSources
@@ -118,7 +120,7 @@ def test_load_timezone_info_minus
     end
 
     def test_load_timezone_info_tainted
-      safe_test do
+      safe_test(unavailable: :skip) do
         identifier = 'Europe/Amsterdam'.dup.taint
         assert(identifier.tainted?)
         info = @data_source.send(:load_timezone_info, identifier)
@@ -227,7 +229,7 @@ def test_load_country_info_case
     end
 
     def test_load_country_info_tainted
-      safe_test do
+      safe_test(unavailable: :skip) do
         code = 'NL'.dup.taint
         assert(code.tainted?)
         info = @data_source.send(:load_country_info, code)
diff --git a/test/data_sources/tc_zoneinfo_data_source.rb b/test/data_sources/tc_zoneinfo_data_source.rb
index b8a40cdd..9da3ede9 100644
--- a/test/data_sources/tc_zoneinfo_data_source.rb
+++ b/test/data_sources/tc_zoneinfo_data_source.rb
@@ -8,6 +8,9 @@
 
 include TZInfo
 
+using TestUtils::TaintExt if TestUtils.const_defined?(:TaintExt)
+using UntaintExt if TZInfo.const_defined?(:UntaintExt)
+
 module DataSources
   class TCZoneinfoDataSource < Minitest::Test
     ZONEINFO_DIR = File.expand_path(File.join(File.dirname(__FILE__), '..', 'zoneinfo')).untaint
@@ -778,7 +781,7 @@ def test_load_timezone_info_linked_relative_parent_inside
     end
 
     def test_load_timezone_info_tainted
-      safe_test do
+      safe_test(unavailable: :skip) do
         identifier = 'Europe/Amsterdam'.dup.taint
         assert(identifier.tainted?)
         info = @data_source.send(:load_timezone_info, identifier)
@@ -1120,7 +1123,7 @@ def test_load_country_info_case
     end
 
     def test_load_country_info_tainted
-      safe_test do
+      safe_test(unavailable: :skip) do
         code = 'NL'.dup.taint
         assert(code.tainted?)
         info = @data_source.send(:load_country_info, code)
diff --git a/test/data_sources/tc_zoneinfo_reader.rb b/test/data_sources/tc_zoneinfo_reader.rb
index 0b916b5f..1c7e10d1 100644
--- a/test/data_sources/tc_zoneinfo_reader.rb
+++ b/test/data_sources/tc_zoneinfo_reader.rb
@@ -6,6 +6,8 @@
 
 include TZInfo
 
+using UntaintExt if TZInfo.const_defined?(:UntaintExt)
+
 module DataSources
   class TCZoneinfoReader < Minitest::Test
     MIN_FORMAT = 1
@@ -1216,10 +1218,10 @@ def test_read_untainted_in_safe_mode
       o0 = TimezoneOffset.new(-12094, 0, 'LT')
 
       tzif_test(offsets, []) do |path, format|
-        # Temp file path is tainted with Ruby >= 2.3.0. Untaint for this test.
-        path.untaint
-
         safe_test do
+          # Temp file path is tainted with Ruby >= 2.3.0. Untaint for this test.
+          path.untaint
+
           assert_equal(o0, @reader.read(path))
         end
       end
@@ -1229,10 +1231,10 @@ def test_read_tainted_in_safe_mode
       offsets = [{gmtoff: -12094, isdst: false, abbrev: 'LT'}]
 
       tzif_test(offsets, []) do |path, format|
-        # Temp file path is only tainted with Ruby >= 2.3.0. Taint for this test.
-        path.taint
-
         safe_test(unavailable: :skip) do
+          # Temp file path is only tainted with Ruby >= 2.3.0. Taint for this test.
+          path.taint
+
           assert_raises(SecurityError) { @reader.read(path) }
         end
       end
diff --git a/test/tc_country.rb b/test/tc_country.rb
index 1783e0bd..61a1b5eb 100644
--- a/test/tc_country.rb
+++ b/test/tc_country.rb
@@ -5,6 +5,8 @@
 
 include TZInfo
 
+using TestUtils::TaintExt if TestUtils.const_defined?(:TaintExt)
+
 class TCCountry < Minitest::Test
   def setup
     @orig_data_source = DataSource.get
@@ -46,7 +48,7 @@ def test_get_nil
   def test_get_tainted_loaded
     Country.get('GB')
 
-    safe_test do
+    safe_test(unavailable: :skip) do
       code = 'GB'.dup.taint
       assert(code.tainted?)
       country = Country.get(code)
@@ -65,7 +67,7 @@ def test_get_tainted_and_frozen_loaded
   end
 
   def test_get_tainted_not_previously_loaded
-    safe_test do
+    safe_test(unavailable: :skip) do
       code = 'GB'.dup.taint
       assert(code.tainted?)
       country = Country.get(code)
diff --git a/test/tc_timezone.rb b/test/tc_timezone.rb
index 55e90716..a6a2d7d1 100644
--- a/test/tc_timezone.rb
+++ b/test/tc_timezone.rb
@@ -5,6 +5,8 @@
 
 include TZInfo
 
+using TestUtils::TaintExt if TestUtils.const_defined?(:TaintExt)
+
 class TCTimezone < Minitest::Test
   class << self
     private
@@ -258,7 +260,7 @@ def test_get_nil
   def test_get_tainted_loaded
     Timezone.get('Europe/Andorra')
 
-    safe_test do
+    safe_test(unavailable: :skip) do
       identifier = 'Europe/Andorra'.dup.taint
       assert(identifier.tainted?)
       tz = Timezone.get(identifier)
@@ -277,7 +279,7 @@ def test_get_tainted_and_frozen_loaded
   end
 
   def test_get_tainted_not_previously_loaded
-    safe_test do
+    safe_test(unavailable: :skip) do
       identifier = 'Europe/Andorra'.dup.taint
       assert(identifier.tainted?)
       tz = Timezone.get(identifier)
diff --git a/test/test_utils.rb b/test/test_utils.rb
index a0d1fce3..d81abda7 100644
--- a/test/test_utils.rb
+++ b/test/test_utils.rb
@@ -49,7 +49,9 @@
   end
 end
 
-TESTS_DIR = File.expand_path(File.dirname(__FILE__)).untaint
+tests_dir = File.expand_path(File.dirname(__FILE__))
+tests_dir.untaint if RUBY_VERSION < '2.7'
+TESTS_DIR = tests_dir
 TZINFO_TEST_ZONEINFO_DIR = File.join(TESTS_DIR, 'zoneinfo')
 
 unless defined? TZINFO_TEST_DATA_DIR
@@ -286,11 +288,11 @@ def without_warnings
 
     # Runs a test with safe mode enabled ($SAFE = 1).
     def safe_test(options = {})
-      # JRuby, Rubinius and TruffleRuby don't support SAFE levels.
-      available = !%w(jruby rbx truffleruby).include?(RUBY_ENGINE)
+      # Ruby >= 2.7, JRuby, Rubinius and TruffleRuby don't support SAFE levels.
+      available = RUBY_VERSION < '2.7' && !%w(jruby rbx truffleruby).include?(RUBY_ENGINE)
 
       if !available && options[:unavailable] == :skip
-        skip('JRuby, Rubinius and TruffleRuby don\'t support SAFE levels')
+        skip('Ruby >= 2.7, JRuby, Rubinius and TruffleRuby don\'t support SAFE levels')
       end
 
       thread = Thread.new do
@@ -482,6 +484,17 @@ def assert_equal_with_offset_and_class(expected, actual)
       assert_equal(expected.class, actual.class)
     end
   end
+
+  # Taint is deprecated in Ruby 2.7 and outputs a warning. Silence the warning.
+  if RUBY_VERSION >= '2.7'
+    module TaintExt
+      refine Object do
+        def taint
+          self
+        end
+      end
+    end
+  end
 end
 
 TestUtils.prepare_test_zoneinfo_dir
diff --git a/test/ts_all_zoneinfo.rb b/test/ts_all_zoneinfo.rb
index 9fe2a261..870a0618 100644
--- a/test/ts_all_zoneinfo.rb
+++ b/test/ts_all_zoneinfo.rb
@@ -7,6 +7,8 @@
 
 # Use a zoneinfo directory containing files needed by the tests.
 # The symlinks in this directory are set up in test_utils.rb.
-TZInfo::DataSource.set(:zoneinfo, File.join(File.expand_path(File.dirname(__FILE__)), 'zoneinfo').untaint)
+zoneinfo_path = File.join(File.expand_path(File.dirname(__FILE__)), 'zoneinfo')
+zoneinfo_path.untaint if RUBY_VERSION < '2.7'
+TZInfo::DataSource.set(:zoneinfo, zoneinfo_path)
 
 require_relative 'ts_all'
diff --git a/test/tzinfo-data2/tzinfo/data.rb b/test/tzinfo-data2/tzinfo/data.rb
index ed808aa1..972cc8db 100644
--- a/test/tzinfo-data2/tzinfo/data.rb
+++ b/test/tzinfo-data2/tzinfo/data.rb
@@ -4,8 +4,11 @@
 module TZInfo
   # Top level module for TZInfo::Data.
   module Data
+    location = File.dirname(File.dirname(__FILE__))
+    location.untaint if RUBY_VERSION < '2.7'
+
     # The directory containing the TZInfo::Data files.
-    LOCATION = File.dirname(File.dirname(__FILE__)).untaint.freeze
+    LOCATION = location.freeze
   end
 end
 
diff --git a/tzinfo.gemspec b/tzinfo.gemspec
index 503687de..364f256d 100644
--- a/tzinfo.gemspec
+++ b/tzinfo.gemspec
@@ -1,4 +1,4 @@
-require File.join(File.expand_path(File.dirname(__FILE__)), 'lib', 'tzinfo', 'version').untaint
+require File.join(File.expand_path(File.dirname(__FILE__)), 'lib', 'tzinfo', 'version')
 
 Gem::Specification.new do |s|
   s.name = 'tzinfo'