diff --git a/prawn.gemspec b/prawn.gemspec
index df1ef5fb3..ff4fe46db 100644
--- a/prawn.gemspec
+++ b/prawn.gemspec
@@ -37,7 +37,7 @@ Gem::Specification.new do |spec|
   spec.licenses = %w[PRAWN GPL-2.0 GPL-3.0]
 
   spec.add_dependency('pdf-core', '~> 0.9.0')
-  spec.add_dependency('ttfunk', '~> 1.6')
+  spec.add_dependency('ttfunk', '~> 1.7')
 
   spec.add_development_dependency('pdf-inspector', '>= 1.2.1', '< 2.0.a')
   spec.add_development_dependency('pdf-reader', ['~> 1.4', '>= 1.4.1'])