diff --git a/app/Jobs/ApplicationDeploymentJob.php b/app/Jobs/ApplicationDeploymentJob.php
index 2c0420144..3c9e12c24 100644
--- a/app/Jobs/ApplicationDeploymentJob.php
+++ b/app/Jobs/ApplicationDeploymentJob.php
@@ -686,8 +686,6 @@ private function deploy_docker_compose_buildpack()
             // Inject build arguments after build subcommand if not using build secrets
             if (! $this->application->settings->use_build_secrets && $this->build_args instanceof \Illuminate\Support\Collection && $this->build_args->isNotEmpty()) {
                 $build_args_string = $this->build_args->implode(' ');
-                // Escape single quotes for bash -c context used by executeInDocker
-                $build_args_string = str_replace("'", "'\\''", $build_args_string);
 
                 // Inject build args right after 'build' subcommand (not at the end)
                 $original_command = $build_command;
@@ -699,9 +697,17 @@ private function deploy_docker_compose_buildpack()
                 }
             }
 
-            $this->execute_remote_command(
-                [executeInDocker($this->deployment_uuid, "cd {$this->basedir} && {$build_command}"), 'hidden' => true],
-            );
+            try {
+                $this->execute_remote_command(
+                    [executeInDocker($this->deployment_uuid, "cd {$this->basedir} && {$build_command}"), 'hidden' => true],
+                );
+            } catch (\RuntimeException $e) {
+                if (str_contains($e->getMessage(), "matching `'") || str_contains($e->getMessage(), 'unexpected EOF')) {
+                    throw new DeploymentException("Custom build command failed due to shell syntax error. Please check your command for special characters (like unmatched quotes): {$this->docker_compose_custom_build_command}");
+                }
+
+                throw $e;
+            }
         } else {
             $command = "{$this->coolify_variables} docker compose";
             // Prepend DOCKER_BUILDKIT=1 if BuildKit is supported
@@ -718,8 +724,6 @@ private function deploy_docker_compose_buildpack()
 
             if (! $this->application->settings->use_build_secrets && $this->build_args instanceof \Illuminate\Support\Collection && $this->build_args->isNotEmpty()) {
                 $build_args_string = $this->build_args->implode(' ');
-                // Escape single quotes for bash -c context used by executeInDocker
-                $build_args_string = str_replace("'", "'\\''", $build_args_string);
                 $command .= " {$build_args_string}";
                 $this->application_deployment_queue->addLogEntry('Adding build arguments to Docker Compose build command.');
             }
@@ -765,9 +769,18 @@ private function deploy_docker_compose_buildpack()
                 );
 
                 $this->write_deployment_configurations();
-                $this->execute_remote_command(
-                    [executeInDocker($this->deployment_uuid, "cd {$this->workdir} && {$start_command}"), 'hidden' => true],
-                );
+
+                try {
+                    $this->execute_remote_command(
+                        [executeInDocker($this->deployment_uuid, "cd {$this->workdir} && {$start_command}"), 'hidden' => true],
+                    );
+                } catch (\RuntimeException $e) {
+                    if (str_contains($e->getMessage(), "matching `'") || str_contains($e->getMessage(), 'unexpected EOF')) {
+                        throw new DeploymentException("Custom start command failed due to shell syntax error. Please check your command for special characters (like unmatched quotes): {$this->docker_compose_custom_start_command}");
+                    }
+
+                    throw $e;
+                }
             } else {
                 $this->write_deployment_configurations();
                 $this->docker_compose_location = '/docker-compose.yaml';
diff --git a/bootstrap/helpers/docker.php b/bootstrap/helpers/docker.php
index 8212f9dc6..77e8b7b07 100644
--- a/bootstrap/helpers/docker.php
+++ b/bootstrap/helpers/docker.php
@@ -139,8 +139,9 @@ function checkMinimumDockerEngineVersion($dockerVersion)
 }
 function executeInDocker(string $containerId, string $command)
 {
-    return "docker exec {$containerId} bash -c '{$command}'";
-    // return "docker exec {$this->deployment_uuid} bash -c '{$command} |& tee -a /proc/1/fd/1; [ \$PIPESTATUS -eq 0 ] || exit \$PIPESTATUS'";
+    $escapedCommand = str_replace("'", "'\\''", $command);
+
+    return "docker exec {$containerId} bash -c '{$escapedCommand}'";
 }
 
 function getContainerStatus(Server $server, string $container_id, bool $all_data = false, bool $throwError = false)
diff --git a/tests/Unit/ExecuteInDockerEscapingTest.php b/tests/Unit/ExecuteInDockerEscapingTest.php
new file mode 100644
index 000000000..14777ca1c
--- /dev/null
+++ b/tests/Unit/ExecuteInDockerEscapingTest.php
@@ -0,0 +1,35 @@
+<?php
+
+it('passes a simple command through correctly', function () {
+    $result = executeInDocker('test-container', 'ls -la /app');
+
+    expect($result)->toBe("docker exec test-container bash -c 'ls -la /app'");
+});
+
+it('escapes single quotes in command', function () {
+    $result = executeInDocker('test-container', "echo 'hello world'");
+
+    expect($result)->toBe("docker exec test-container bash -c 'echo '\\''hello world'\\'''");
+});
+
+it('prevents command injection via single quote breakout', function () {
+    $malicious = "cd /dir && docker compose build'; id; #";
+    $result = executeInDocker('test-container', $malicious);
+
+    // The single quote in the malicious command should be escaped so it cannot break out of bash -c
+    // The raw unescaped pattern "build'; id;" must not appear — the quote must be escaped
+    expect($result)->not->toContain("build'; id;");
+    expect($result)->toBe("docker exec test-container bash -c 'cd /dir && docker compose build'\\''; id; #'");
+});
+
+it('handles empty command', function () {
+    $result = executeInDocker('test-container', '');
+
+    expect($result)->toBe("docker exec test-container bash -c ''");
+});
+
+it('handles command with multiple single quotes', function () {
+    $result = executeInDocker('test-container', "echo 'a' && echo 'b'");
+
+    expect($result)->toBe("docker exec test-container bash -c 'echo '\\''a'\\'' && echo '\\''b'\\'''");
+});