diff --git a/pkgs/development/python-modules/dulwich/default.nix b/pkgs/development/python-modules/dulwich/default.nix
index ea3511e843a3..570598e1a993 100644
--- a/pkgs/development/python-modules/dulwich/default.nix
+++ b/pkgs/development/python-modules/dulwich/default.nix
@@ -17,7 +17,7 @@
 }:
 
 buildPythonPackage rec {
-  version = "0.20.40";
+  version = "0.20.42";
   pname = "dulwich";
   format = "setuptools";
 
@@ -25,7 +25,7 @@ buildPythonPackage rec {
 
   src = fetchPypi {
     inherit pname version;
-    hash = "sha256-vtcO/gt91RpHvOqbmEqwamdddDi3izLaHLr891D7utc=";
+    hash = "sha256-cro7YK5qVU0TMrO0CjRf6+FuxGnPYBS7RDtxmQLjPvA=";
   };
 
   LC_ALL = "en_US.UTF-8";