diff --git a/pkgs/development/libraries/libsass/default.nix b/pkgs/development/libraries/libsass/default.nix
index 9efe07c6567..75bc9668fca 100644
--- a/pkgs/development/libraries/libsass/default.nix
+++ b/pkgs/development/libraries/libsass/default.nix
@@ -2,11 +2,11 @@
 
 stdenv.mkDerivation rec {
   name = "libsass-${version}";
-  version = "3.3.2";
+  version = "3.4.5";
 
   src = fetchurl {
     url = "https://github.com/sass/libsass/archive/${version}.tar.gz";
-    sha256 = "affb7efaa7e152e576cc1d510c662ebe067b0b9e9228ad2937dcafdd4431b573";
+    sha256 = "1j22138l5ymqjfj5zan9d2hipa3ahjmifgpjahqy1smlg5sb837x";
   };
 
   patchPhase = ''
diff --git a/pkgs/development/tools/sassc/default.nix b/pkgs/development/tools/sassc/default.nix
index 1e990b0e2e9..eb82cf84966 100644
--- a/pkgs/development/tools/sassc/default.nix
+++ b/pkgs/development/tools/sassc/default.nix
@@ -2,11 +2,11 @@
 
 stdenv.mkDerivation rec {
   name = "sassc-${version}";
-  version = "3.3.2";
+  version = "3.4.5";
 
   src = fetchurl {
     url = "https://github.com/sass/sassc/archive/${version}.tar.gz";
-    sha256 = "15a2b2698639dfdc7bd6a5ba7a9ecdaf8ebb9f15503fb04dea1be3133308e41d";
+    sha256 = "1xk4kmmvziz9sal3swpqa10q0s289xjpcz8aggmly8mvxvmngsi9";
   };
 
   patchPhase = ''