Added an event for default stable rule 'Drop and execute new binary in container'

events/syscall/drop_and_execute_new_binary_in_container.go

@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: Apache-2.0
+/*
+Copyright (C) 2024 The Falco Authors.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+    http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package syscall
+
+import (
+	"os"
+	"os/exec"
+
+	"github.com/falcosecurity/event-generator/events"
+)
+
+var _ = events.Register(DropAndExecuteNewBinaryInContainer)
+
+func DropAndExecuteNewBinaryInContainer(h events.Helper) error {
+	if h.InContainer() {
+		// Find the path of the ls binary
+		lsPath, err := exec.LookPath("ls")
+		if err != nil {
+			h.Log().WithError(err).Error("ls binary not found")
+			return err
+		}
+
+		// Read the ls binary content
+		lsContent, err := os.ReadFile(lsPath)
+		if err != nil {
+			return err
+		}
+
+		// New binary which is duplicate of ls binary
+		newBinaryPath := "/bin/ls-created-by-event-generator"
+
+		err = os.WriteFile(newBinaryPath, lsContent, 0755)
+		if err != nil {
+			h.Log().WithError(err).Error("failed to create new file in /bin")
+			return err
+		}
+		defer os.Remove(newBinaryPath) // CleanUp
+
+		executeCmd := exec.Command(newBinaryPath)
+		h.Log().Info("Executed a binary not part of base image")
+		executeCmd.Run() // Rule triggers even the command is not successful
+	}
+	return nil
+}