Aliyun account purchase: ECS enterprise-level security reinforcement: cloud shield configuration, DDoS prevention and vulnerability repair
In the wave of enterprise digital transformation, cloud server (ECS) has become the nerve center of the core business system of the enterprise. Whether it is a highly concurrent e-commerce platform, a financial interface that processes massive amounts of data on a daily basis, or as the underlying cornerstone of an enterprise's internal SaaS system, ECS carries not only code and data, but also the business lifeblood of the enterprise.
However, the public network environment has never been a safe haven. Hackers' automated scanning scripts, daily DDoS traffic peaks, and quietly spreading system high-risk vulnerabilities are always threatening the survival of enterprise cloud assets. For the operation and security team, the simple "install anti-virus software" has long been unable to deal with complex cloud threats. How to in
Alibaba Cloud server purchase
After completion, build a set of enterprise-level security reinforcement system with defense-in-depth capability from scratch?
This article will deeply disassemble Alibaba Cloud's native security ecology, focusing on
Apsara Stack Security Center (Apsara Stack Security Center) configuration, anti-DDoS solution design, and vulnerability lifecycle remediation
The three core battles show you a real cloud security protection guide that can be implemented and meets the requirements of enterprise compliance and actual combat.
Battle 1: Deep configuration and baseline reinforcement of Alibaba Cloud Security (Cloud Security Center)
Many companies are
Alibaba Cloud server purchase
After the ECS deployment service is opened, the in-depth configuration of the cloud shield (cloud security center) is often ignored, and only stays in the initial stage of "installing Agent and receiving alarms. In fact, as the "security brain" of cloud assets, the greatest value of cloud shield lies in advance defense and real-time threat convergence.
1. Client Agent deployment and health inspection
When you create an ECS instance, the installation AliYunDun (Cloud Security Center Agent) is selected by default. However, in an enterprise-level multi-account, hybrid cloud, or complex VPC network environment, the Agent must be absolutely online.
Self-healing mechanism check: Ensure that AliYunDun and AliYunDunUpdate processes are resident in the background. If the Agent is disconnected, the security console cannot perceive it even if the attacker invades the system.
Network access whitelist: If the outbound traffic of ECS is strictly controlled in the security group or local firewall (for example, all Outbound traffic is denied by default), you must ensure that the domain name and IP access channel of the cloud security center server are opened to avoid "blindness" of the security client ".
2. Security baseline scanning and compliance governance
Cloud Security Center has built-in baseline check templates that cover CIS (Internet Security Center) standards, equal protection 2.0 (Level 3/Level 4), and Alibaba Cloud best practices.
Identity and Access Management (IAM): Do not use the root account to log in directly through SSH. Force the SSH key pair (Key-Pair) authentication of ordinary users and configure sudo permission approval.
Weak password and account audit: Enable network-wide weak password detection in the baseline policy to check the system account.
3. The database account (MySQL/Redis/MongoDB) is forcibly scanned regularly to eliminate low-level vulnerabilities such as "empty password" or "admin/123456.
Abnormal login behavior blocking: Leverage Alibaba Cloud Security’s “Common Logon Locations” and “Common IPs” configuration features. Once a remote login or an SSH/RDP brute force attack request from an unknown IP address is detected, the automatic blocking policy is triggered to block the attack IP address at the edge of the cloud platform.
3. Alert Policy Convergence and SOAR Automated Response
In production environments, alert fatigue is a nightmare for operations and maintenance personnel. Security teams need to set clear governance priorities for threat levels:
Urgent (High): For example, rebound shell, Webshell implantation, and blackmail virus encryption behavior, the victim instance must be isolated at the second level in combination with the Anti-Tampering and Automated Response Script (SOAR) of Cloud Security Center.
Major/Minor (Medium/Low): If unnecessary port opening or expired certificate warning, convergence to weekly security weekly report for batch troubleshooting.
Part Two: DDoS Attack Defense — From Basic Protection to High-Defense Architectures
Distributed Denial of Service (DDoS) attacks are the most direct and destructive attack method for businesses on the cloud. Attackers control the botnet to dump tens or even hundreds of Gbps of junk traffic to the target server, directly exploding server bandwidth resources or TCP connection pools, resulting in normal users unable to access.
Upon completion
Alibaba Cloud server purchase
After that, enterprises should plan a stepped anti-DDoS system according to the sensitivity of their business and the risk level of attack.
[Internet Public Network Traffic]
│
▼
┌──────────────────────────────────────────────┐
│ First Line of Defense: DDoS Basic Protection (Free 5Gbps Cleaning) │ (Near Source Traffic Cleaning)
└──────────────────────┬───────────────────────┘
│ Traffic> 5Gbps
▼
┌──────────────────────────────────────────────┐
│ Second Line of Defense: DDoS Native Protection/DDoS High Protection (BGP) │ (Mass Cleaning & AI Filtering)
└──────────────────────┬───────────────────────┘
│ Application-layer protocol attack (CC)
▼
┌──────────────────────────────────────────────┐
│ Third Line of Defense: Web Application Firewall (WAF) │ ─ ─ ─(HTTP/HTTPS Refined Protection)
└──────────────────────┬───────────────────────┘
Clean traffic
▼
┌──────────────────────────────────────────────┐
│ Target Assets: Alibaba Cloud ECS Instances/SLB Load Balancers │
└──────────────────────────────────────────────┘
1. Fine-tuning of Anti-DDoS Basic Protection (Free Edition)
Alibaba Cloud provides free basic DDoS protection for all ECS instances by default (usually providing protection of up to about 5Gbps). Many operation and maintenance personnel think that "everything will be fine if it is turned on by default", but ignore the optimization of the cleaning threshold.
Default threshold: The default BPS (bits per second) and PPS (packets per second) cleaning thresholds are usually based on the maximum specifications of the ECS. For small ECS instances, the traffic may not reach the default cleaning threshold, and the CPU or NIC of the server may have been washed away.
Manual optimization policy: In-depth analysis of the daily peak traffic of the business, in the Cloud Security Center console, manually adjust the BPS and PPS cleaning thresholds to 1.5 - 2 times the normal peak. Once the sudden traffic exceeds the normal business curve, the cloud traffic cleaning is triggered immediately.
2. Understanding the “Black Hole Strategy” and Risk-Hedging Mechanisms
When the attack traffic far exceeds the free protection limit (for example, more than 5Gbps), to protect the security of the public network of the cloud data center, Alibaba Cloud will move the public IP of the target ECS instance into the "black hole" and discard all traffic entering the IP.
The default duration of a black hole usually ranges from 2 hours to 24 hours, during which time the business will be completely interrupted.
Mitigation strategy: For core business systems, never directly expose the ECS public IP address in DNS resolution. You should use SLB (load balancing) as the entrance, or mount Alibaba Cloud WAF(Web Application Firewall) and CDN/full-site acceleration on the front end. The real ECS IP address is hidden inside the VPC intranet to significantly reduce the risk of being directly paralyzed by a black hole.
3. Enterprise‑Level Multi‑Pronged Defense Against High‑Volume Attacks
For gaming, finance, and electricity
In vulnerable industries such as businesses and cross-border businesses, it is far from enough to rely solely on ECS's own protection:
DDoS native protection: It is suitable for large and medium-sized enterprises with multiple public network IP assets (such as ECS, SLB, EIP). It does not need to change the existing network architecture and IP deployment. It can directly upgrade the protection of native IP on the cloud and enjoy Tbps protection capability.
DDoS high protection (Anti-DDoS Pro/Premium): BGP lines or overseas Anycast nodes are used to pull all public network traffic to the high protection computer room for malformed message filtering, SYN Flood interception and CC attack management through DNS domain name resolution (CNAME) or IP drainage. The cleaned clean traffic is then returned to the back-end ECS through dedicated lines or back-to-source IP.
Battle 3: Full lifecycle management of vulnerabilities-best practices for vulnerability remediation on the cloud
If DDoS is an external brute force tearing down walls, then vulnerabilities are backdoor keys left to attackers. Vulnerabilities in operating systems (such as the Linux kernel and Windows system patches), open source components (such as Log4j2, OpenSSL, and Redis), and application layer code are the main channels for intrusion of enterprise cloud assets.
When fixing vulnerabilities on the cloud, you must not take the crude approach of "finding one and directly updating the installation. The most taboo in the production environment is the business crash or the system cannot be started due to patch incompatibility.
1. Vulnerability classification and prioritization (Vulnerability Triage)
Security Center will scan vulnerabilities into three categories:
Linux software vulnerabilities/Windows system vulnerabilities, such as Apache, Nginx, OpenSSH, and Windows remote code execution vulnerabilities (CVE).
Application vulnerabilities (Web vulnerabilities): such as SQL injection, XSS, cross-site request forgery, and deserialization vulnerabilities.
Emergency vulnerability: The global explosive Zero-Day vulnerability of the Alibaba Cloud security team.
Repair priority should follow
"CVSS Score Asset Importance Exposures"
Three-dimensional determination principle: High-risk CVE that is directly exposed to the public network and has remote code execution (RCE) or privilege elevation (Privilege Escalation) must be repaired or mitigated within 24 hours.
2. Enterprise-level "zero downtime" vulnerability repair standard process
When performing vulnerability remediation, strictly follow the following standard SOP procedures:
Step 1: Create an ECS system snapshot (full backup)
When performing software updates on any production environment ECS (especially
yum update
,
apt upgrade
or install kernel patch),
The system disk (and the necessary disks) of the target ECS must be
Manually create a snapshot
.
Alibaba Cloud snapshot is the last card for "one-click rollback" after a repair failure.
Step 2: Environment isolation and pre-release verification
Do not "one-click repair" directly in the production environment ". The production instance should be cloned into a test machine without public network through the ECS mirroring function. In the test environment, patch installation and business automation test set should be executed first to ensure the stable operation of core application interface, database connection and middleware.
Step 3: Use the cloud security center "one-click repair" and OOS to automate operation and maintenance.
For Linux software vulnerabilities and Windows patches, Cloud Security Center Paid Edition provides the "automatic snapshot creation and repair" function.
For large-scale ECS clusters, you can set automatic patching and rotation restart policies for off-peak business periods (such as 2:00 a.m. -4:00 a.m.) in conjunction with "Patch Manager" of Aliyun System Operation and Maintenance Management (OOS).
Bash
# Example: Take turning off interactive prompts before Ubuntu system repair as an example
export DEBIAN_FRONTEND=noninteractive
# Perform vulnerability fix upgrade
sudo apt-get update && sudo apt-get --only-upgrade install openssh-server -y
# Verify the service status after the vulnerability is fixed
systemctl status sshd
Step 4: Grayscale release and effect verification
After fixing the production environment, return to the Security Center console and click
"Validate"
Button. Security Center will initiate targeted scanning again to confirm that the vulnerability status is fixed ".
The fourth battle: cloud system defense-in-depth system landing list
In order to help enterprise security and operation and maintenance managers sort out the security reinforcement actions at a glance, the following is the completion.
Alibaba Cloud server purchase
After that, the standard verification matrix for enterprise-level ECS reinforcement:
Protection level
Reinforcement dimension
Core Operating Requirements
Recommended Alibaba Cloud security products/features
network boundary
Security group (Security group)
Implement the "least privilege principle" and deny all inbound traffic by default. Disable 0.0.0.0/0 to open sensitive ports such as 22/3389/3306. Work with VPC to divide subnets.
Alibaba Cloud security group/VPC logical isolation
Traffic Defense
DDoS attack protection
Manually fine-tune the BPS/PPS cleaning threshold, hide the IP address of the source station, and configure high-security CNAME drainage for large-traffic services.
Anti-DDoS Basic Protection/DDoS High-Defense
Application Security
Web Attack and CC Interception
Preventing SQL injection, webshell uploads, OW
ASP Top 10 threats; enable Bot traffic management and API security detection.
Alibaba Cloud Web Application Firewall (WAF)
Host Security
System and Baseline Reinforcement
Disable direct root connection; configure SSH key authentication; enable log auditing; regularly perform baseline scanning and weak password troubleshooting.
Cloud Security Center (Alibaba Cloud Security)
Vulnerability Governance
Full life cycle repair
Adhere to the principle of "snapshot before repair"; Establish a pre-release test mechanism; Use automated operation and maintenance components for low-peak patching.
Security Center Vulnerability Management OOS Patch Management
Data security
Backup and Disaster Recovery
Configure automatic snapshot policies for system disks and data disks; enable cross-zone/cross-region disaster recovery backup for core databases.
Cloud server ECS snapshot/cloud backup (DBS)
Summary: from "passive fire fighting" to "active safety"
The ultimate goal of cloud security is never to create absolutely no vulnerabilities, but to establish a dynamic security defense system with "timely detection, rapid response, defense depth, and complete backup and disaster tolerance.
When the business is completed
Alibaba Cloud server purchase
And ready to deploy the business from the moment, security reinforcement work should be started simultaneously. By reasonably configuring the cloud shield (cloud security center) to build a sensitive awareness system of assets, deploying stepped anti-DDoS solutions to guard the network gate, and implementing standardized and standardized SOP to perform vulnerability repair and baseline reinforcement, enterprises can truly "sit firmly in the fishing boat against the wind and waves" in the increasingly severe network security environment and provide indestructible security escort for the rapid speeding of business.
