diff --git a/pkgs/mattermost.nix b/pkgs/mattermost.nix
index 5bc519a..ededbec 100644
--- a/pkgs/mattermost.nix
+++ b/pkgs/mattermost.nix
@@ -12,13 +12,13 @@ buildGoModule rec {
   # See https://docs.mattermost.com/upgrade/extended-support-release.html
   # When a new ESR version is available (e.g. 8.1.x -> 9.5.x), update
   # the version regex in passthru.updateScript as well.
-  version = "9.5.5";
+  version = "9.5.6";
 
   src = fetchFromGitHub {
     owner = "mattermost";
     repo = "mattermost";
     rev = "v${version}";
-    hash = "sha256-ZaFXuYm9SEE9ARN5PG8vjt9WnNfGiALilGzjfnDP7aA=";
+    hash = "sha256-bLnvbduP6h9o82BQUNh9MyFpW/Cbl6c5o9hrPV0Z8+0=";
   };
 
   # Needed because buildGoModule does not support go workspaces yet.
@@ -34,7 +34,7 @@ buildGoModule rec {
 
   webapp = fetchurl {
     url = "https://releases.mattermost.com/${version}/mattermost-${version}-linux-amd64.tar.gz";
-    hash = "sha256-tgds8eTBeisuJcLgtx6zOiFUcVL1oU0LLbPqmh4SQUU=";
+    hash = "sha256-ZlvO/7kdMopIHBDdFp6wSQCR+NobGdDC6PcVd1iG16E=";
   };
 
   vendorHash = "sha256-TJCtgNf56A1U0EbV5gXjTro+YudVBRWiSZoBC3nJxnE=";
@@ -77,7 +77,7 @@ buildGoModule rec {
   meta = with lib; {
     description = "Mattermost is an open source platform for secure collaboration across the entire software development lifecycle";
     homepage = "https://www.mattermost.org";
-    license = with licenses; [ agpl3 asl20 ];
+    license = with licenses; [ agpl3Only asl20 ];
     maintainers = with maintainers; [ ryantm numinit kranzes mgdelacroix ];
     mainProgram = "mattermost";
   };