diff --git a/docker-compose.yml b/docker-compose.yml
index b3b153d6679..759afe8ded0 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -36,17 +36,18 @@ x-op-backend: &backend
     target: develop
   <<: [*image, *restart_policy]
   environment:
+    DATABASE_URL: postgresql://${DB_USERNAME:-postgres}:${DB_PASSWORD:-postgres}@${DB_HOST:-db}:${DB_PORT:-5432}/${DB_DATABASE:-openproject}?pool=100
     LOCAL_DEV_CHECK: "${LOCAL_DEV_CHECK:?The docker-compose file for OpenProject has moved to https://github.com/opf/openproject-docker-compose}"
-    RAILS_ENV: development
     OPENPROJECT_CACHE__MEMCACHE__SERVER: cache:11211
+    OPENPROJECT_EDITION: ${OPENPROJECT_EDITION:-standard}
     OPENPROJECT_RAILS__CACHE__STORE: file_store
     OPENPROJECT_RAILS__RELATIVE__URL__ROOT: "${OPENPROJECT_RAILS__RELATIVE__URL__ROOT:-}"
-    DATABASE_URL: postgresql://${DB_USERNAME:-postgres}:${DB_PASSWORD:-postgres}@${DB_HOST:-db}:${DB_PORT:-5432}/${DB_DATABASE:-openproject}?pool=100
-    OPENPROJECT_EDITION: ${OPENPROJECT_EDITION:-standard}
+    OPENPROJECT_SSRF_PROTECTION_IP_ALLOWLIST: 0.0.0.0/0,::0/0 # disabling SSRF in dev to not interfere with local integrations (Nextcloud etc.)
     OPENPROJECT_WEB_MAX__THREADS: 1
     OPENPROJECT_WEB_MIN__THREADS: 1
     OPENPROJECT_WEB_WORKERS: 0
     PIDFILE: /home/dev/openproject/tmpfs/pids/server.pid
+    RAILS_ENV: development
   volumes:
     - ".:/home/dev/openproject"
     - "opdata:/var/openproject/assets"
diff --git a/lib/open_project.rb b/lib/open_project.rb
index 149308044e4..0a098499416 100644
--- a/lib/open_project.rb
+++ b/lib/open_project.rb
@@ -34,6 +34,7 @@ require "open_project/patches"
 require "open_project/mime_type"
 require "open_project/custom_styles/design"
 require "open_project/httpx_appsignal"
+require "open_project/httpx_ssrf_filter"
 require "redmine/plugin"
 
 require "csv"
@@ -62,6 +63,7 @@ module OpenProject
                 .with(headers: { "User-Agent" => "OpenProject #{OpenProject::VERSION.to_semver} HTTPX Client" })
                 .plugin(:auth)
                 .plugin(:webdav)
+                .plugin(HttpxSsrfFilter)
                 .with(
                   timeout: {
                     connect_timeout: OpenProject::Configuration.httpx_connect_timeout,
diff --git a/lib/open_project/httpx_ssrf_filter.rb b/lib/open_project/httpx_ssrf_filter.rb
new file mode 100644
index 00000000000..be7545c6429
--- /dev/null
+++ b/lib/open_project/httpx_ssrf_filter.rb
@@ -0,0 +1,57 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+module OpenProject
+  # An SSRF filter for HTTPX based on the original plugin.
+  # See https://gitlab.com/os85/httpx/-/blob/master/lib/httpx/plugins/ssrf_filter.rb
+  #
+  # The main difference is that we use our own subclass of `SsrfFilter` to perform the matching of unsafe IP addresses.
+  # We are thus consulting our own allow list of IP addresses before blocking an IP address.
+  module HttpxSsrfFilter
+    class ServerSideRequestForgeryError < HTTPX::Error; end
+
+    module ConnectionMethods
+      def initialize(*)
+        super
+      rescue ServerSideRequestForgeryError => e
+        # may raise when IPs are passed as options via :addresses
+        throw(:resolve_error, e)
+      end
+
+      def addresses=(addrs)
+        addrs.reject!(&SsrfProtection.method(:unsafe_ip_address?)) # rubocop:disable Performance/MethodObjectAsBlock
+
+        raise ServerSideRequestForgeryError, "#{@origin.host} has no public IP addresses" if addrs.empty?
+
+        super
+      end
+    end
+  end
+end
diff --git a/spec/lib/open_project_spec.rb b/spec/lib/open_project_spec.rb
new file mode 100644
index 00000000000..22abc49b730
--- /dev/null
+++ b/spec/lib/open_project_spec.rb
@@ -0,0 +1,74 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+require "spec_helper"
+
+RSpec.describe OpenProject do
+  describe ".httpx" do
+    subject(:httpx) { described_class.httpx }
+
+    let(:public_endpoint) { "https://openproject.org/rspec-test" }
+    let(:private_endpoint) { "https://localhost/rspec-test" }
+
+    it "sets a proper User-Agent header", :webmock do
+      stub_request(:get, public_endpoint).to_return(status: 204)
+
+      httpx.get(public_endpoint)
+      expect(WebMock).to have_requested(:get, public_endpoint)
+        .with(headers: { "User-Agent": /OpenProject \d+\.\d+\.\d+ HTTPX Client/ })
+    end
+
+    # We can't use webmock for these tests, as it would interfere too early and thus we couldn't test
+    # whether corresponding requests would've been made
+    describe "SSRF filtering" do
+      it "includes SSRF filtering for private IP addresses" do
+        result = httpx.get(private_endpoint)
+        expect(result.error).to be_a(OpenProject::HttpxSsrfFilter::ServerSideRequestForgeryError)
+      end
+
+      it "does not filter requests to public IP addresses" do
+        result = httpx.get(public_endpoint)
+        expect(result.error).to be_nil
+      end
+
+      context "when local IP addresses are allowed" do
+        before do
+          allow(OpenProject::Configuration).to receive(:ssrf_protection_ip_allowlist)
+            .and_return([IPAddr.new("127.0.0.1"), IPAddr.new("::1")])
+        end
+
+        it "does not filter local requests" do
+          result = httpx.get(private_endpoint)
+          expect(result.error).not_to be_a(OpenProject::HttpxSsrfFilter::ServerSideRequestForgeryError)
+        end
+      end
+    end
+  end
+end