diff --git a/pkgs/development/libraries/botan/unstable.nix b/pkgs/development/libraries/botan/unstable.nix
index 172c18480ad..b3fd76ab20c 100644
--- a/pkgs/development/libraries/botan/unstable.nix
+++ b/pkgs/development/libraries/botan/unstable.nix
@@ -2,7 +2,7 @@
 
 callPackage ./generic.nix (args // {
   baseVersion = "1.11";
-  revision = "25";
-  sha256 = "1spjryza9yznbsa26i1kg3hz4ifjdi6cjhfd2h2lqg07xyf2a66c";
+  revision = "28";
+  sha256 = "0cjr3zkara8js1fbm8ddcbd5mkizxh1wm6fja13psw5j8mpwj554";
   openssl = null;
 })