Vulnerability management overview
Vulnerability Management automates the discovery, assessment, and remediation of security vulnerabilities on your servers. To help you manage security risks and reduce your system's attack surface, it covers operating systems (OS) and various applications. Vulnerability Management provides automated scanning and fixes, replacing traditional manual patching and making it ideal for managing large-scale server clusters.
Use cases
Continuous and automated vulnerability management for critical business servers
Scenario: Critical business servers require daily vulnerability scans and timely fixes to keep services secure and stable.
Applicable editions: Advanced, Enterprise, or Ultimate.
Features: Supports one automatic periodic vulnerability scan per day and unlimited vulnerability fixes. It also supports manual vulnerability scans to address sudden security incidents.
Basic protection for non-core servers or development environments
Scenario: You need basic vulnerability detection and fixing for a small number of servers (fewer than 10) or for development and testing environments, while keeping costs low.
Applicable editions: Anti-virus, with an option to Purchase vulnerability fixes on demand.
Features: Supports one automatic periodic vulnerability scan every two days, meeting basic needs. When you need to fix vulnerabilities, you can use the pay-as-you-go model or purchase a fix package for flexible vulnerability management.
Rapidly respond to and investigate newly disclosed critical vulnerabilities
Scenario: When a major security vulnerability (such as Log4j2) is disclosed, you need to immediately determine if any of your server assets are affected.
Applicable editions: Enterprise or Ultimate.
Features: Use the manual vulnerability scan to immediately run a comprehensive scan on all or a subset of your servers. The scan results provide detailed vulnerability information and official remediation advice for manual fixes.
Core features
Vulnerability scan
Vulnerability Scan supports two methods: manual vulnerability scan and periodic automatic vulnerability scan.
Comparison | Manual vulnerability scan | Periodic automatic vulnerability scan |
Trigger method | Users initiate scans on demand from the console. | The system automatically runs scans at scheduled intervals based on a preset policy. |
Scan frequency | Not fixed; determined by the user. | Advanced, Enterprise, and Ultimate Edition: Daily by default. Basic Edition and other editions: Every two days by default. |
Use cases | • Emergency response: Quickly investigate newly disclosed high-risk vulnerabilities. • Post-change verification: Verify system security immediately after deploying new applications or updates. | • Routine inspection: For continuous, automated vulnerability monitoring to meet compliance requirements. • Centralized management: Regularly receive vulnerability reports for all assets without manual intervention. |
Vulnerability fixing
Security Center provides a One-click Fix capability that automatically deploys a patch to help you resolve security issues quickly.
A Windows cumulative security update is a package in which Microsoft combines multiple fixes. Its title usually contains "Cumulative Update." An operating system patch is a standalone update for a specific issue.
Fixing methods
One-click fix: Security Center provides a one-click fix feature in the console. This feature helps you automate vulnerability fixing without needing to log on to servers and perform manual operations.
ImportantThe one-click fix feature is not supported for Application Vulnerability and Urgent Vulnerability.
Automatic fix: You can turn on the Automatic Vulnerability Remediation switch and configure automatic fixing tasks to periodically fix newly discovered vulnerabilities within a specified period.
Automatic fixing tasks depend on the one-click fix feature. If the current edition or vulnerability type does not support one-click fix, automatic fixing is also not supported.
Automatic fixing is supported only for non-kernel Linux system vulnerabilities.
Manual fix: If the current edition or vulnerability type does not support one-click fix, or if the Remaining Vulnerability Fixes feature is not enabled, you must log on to the server and follow the fixing suggestions in the vulnerability details to manually fix the vulnerability.
Vulnerability fix calculation rules
Minimum unit: Successfully fixing one Security Notice on one server counts as one fix.
ImportantA single Security Notice may contain multiple related CVEs. Fixing the notice counts as only 1 fix, regardless of how many CVEs it includes.
Number of vulnerability fixes = Σ (Number of Security Notices with the "Fixed" status on each server)
ImportantA fix is counted only after the server restarts and its status changes to "Fixed". Failed fixes are not counted.
Example:
If you use Security Center to successfully fix 10 different Security Notices on each of 5 servers:
Total vulnerability fixes = 5 servers × 10 Security Notices = 50 fixes
Vulnerability fix priority
When vulnerabilities exist, the Alibaba Cloud vulnerability scoring system (based on CVSS and combined with real-world cloud attack scenarios) helps you prioritize fixes. This system considers a vulnerability's severity, exploit maturity, threat risk, and the scope of affected assets.
Vulnerability Remediation Urgency Score = Alibaba Cloud Vulnerability Score × Time Factor × Environment Factor × Asset Importance Factor.
Alibaba Cloud Vulnerability Score: Evaluates the inherent severity of the vulnerability.
Time Factor: Considers dynamic factors like the vulnerability's disclosure date and the prevalence of exploit methods (value from 0 to 1).
Environment Factor: Assesses the vulnerability's exploitability in the server environment, such as whether it is connected to the public internet (value is dynamically adjusted).
Asset Importance Factor: Adjusts the priority based on the asset's importance setting (Important: 1.5, General: 1, Test: 0.5).
Fix priority and suggestions:
Priority
Remediation urgency score
Description
Remediation suggestion
High
13.5 or higher
Easily exploitable by an unauthenticated remote attacker, leading to system compromise (e.g., arbitrary code execution) without user interaction. Often used by worms and ransomware.
Fix as soon as possible
Medium
7.1 to 13.5
Potentially compromises the confidentiality, integrity, or availability of resources. Typically includes vulnerabilities with high official ratings but are not yet demonstrably exploitable.
Can be fixed later
Low
Below 7
Extremely low probability of successful exploitation or no real risk if exploited. Common in source code bugs or vulnerabilities with minor impacts on compliance or business performance.
Can be postponed
Special
-
Urgent Vulnerability: High-risk vulnerabilities confirmed by Alibaba Cloud security engineers. We recommend you fix them as soon as possible. When the environment factor cannot be obtained due to network issues, the suggestion may display as "Can be postponed."
Fix as soon as possible
Detection rules and data management policy
Rule update schedule
To cover new Security Notices from OS vendors, Security Center regularly updates its vulnerability detection rules.
Vulnerability updates may be delayed during public holidays.
Linux Systems:
High-risk vulnerabilities: Detection rules are added within 48 hours of the OS vendor's announcement.
CVE vulnerabilities: Detection rules are added within 14 days of the OS vendor's announcement.
Windows Systems: CVE vulnerability detection rules are added within 48 hours of Microsoft's announcement.
Data retention policy
To ensure efficient system performance, Security Center automatically cleans up stale vulnerability data.
Active vulnerabilities:
If a vulnerability's status (e.g., Fixed, Fixing Failed, Ignored, Unfixed, Fixing, Verifying) does not change for one year, the system automatically deletes the vulnerability record.Invalid vulnerabilities:
The system automatically deletes a vulnerability record if its status remains Invalid for longer than the retention period defined in Retain Invalid Vulnerabilities For under Vulnerability Settings.
Billing
Security Center offers two billing models for its vulnerability scanning and fixing features: Subscription and Pay-as-you-go. For more details, see Billing description.
To activate vulnerability scanning and fixing, you must associate your servers with an edition or protection level after purchase. For instructions, see Configure protection editions or levels.
Subscription: Purchase an edition or a Vulnerability Fixing value-added service.
Pay-as-you-go: Purchase Host and Container Security or the Vulnerability Fixing post-paid feature.
The supported feature scope varies by model, as shown in the table below:
Billing model | Edition / Protection level | Manual scan scope | Periodic automatic scan scope | Vulnerability fixing capability |
Subscription | Enterprise Edition, Ultimate Edition | All | All | Supports fixing Linux and Windows vulnerabilities. |
Advanced Edition | All vulnerabilities except Application Vulnerability. | All vulnerabilities except Application Vulnerability. | Supports fixing Linux and Windows vulnerabilities. | |
Basic Edition, Value-added Edition, Anti-virus Edition | Urgent Vulnerability only. | Linux Software Vulnerability, Windows System Vulnerability. | Important To enable One-click Fix, you must purchase the separate Remaining Vulnerability Fixes value-added service. For instructions, see Purchase Vulnerability Fixing (Subscription) and Activate Vulnerability Fixing (Pay-as-you-go). After purchase, supports fixing Linux and Windows vulnerabilities. | |
Pay-as-you-go | Host Protection, Host and Container Protection | All | All | |
Unprotected, Anti-Virus | Urgent Vulnerability only. | Linux Software Vulnerability, Windows System Vulnerability. |
Get started
Purchase and activate Vulnerability Management: Purchase Security Center.
Associate your servers with an edition or protection level: Configure protection editions or levels.
Scan for vulnerabilities: Vulnerability scanning.
Handle vulnerabilities: Manage vulnerabilities.
Troubleshoot failures: Troubleshoot causes of vulnerability fixing failures.
FAQ
How do I view the vulnerabilities that can be detected?
On the Vulnerabilities page, click the number in the Disclosed Vulnerabilities section to view the list of supported vulnerabilities.
Security Center does not provide separate vulnerability rule database or host rule database version numbers. The current scope of supported vulnerability scanning is the one shown in real time in the Disclosed Vulnerabilities list in the console.
Does Security Center scan website code vulnerabilities, such as arbitrary file download vulnerabilities, check TLS protocol compliance, or provide manual remediation services?
Alibaba Cloud Security Center vulnerability management covers system vulnerability detection for servers, Linux software vulnerability detection, application vulnerability detection, and urgent vulnerability detection. It does not scan specific web application logic vulnerabilities, such as arbitrary file download vulnerabilities, or check TLS protocol compliance. It does not provide manual website code vulnerability remediation or automatic operating system or web application hardening.
For web application protection, deploy Web Application Firewall (WAF). To fix code vulnerabilities, follow the remediation suggestions in the vulnerability details, such as validating input paths and restricting accessible directories. For system hardening, manually configure your system by following the official documentation.
What do I do if vulnerability fix verification reports that I am not authorized, or an instance still shows Free Edition after I purchase Enterprise Edition?
The authorization message usually appears because the server is associated with Free Edition, the number of protection licenses is insufficient, or the container environment is not associated with Ultimate Edition. Upgrade the edition and increase the number of licenses. For a container environment, upgrade to Ultimate Edition. You can also start a one-click urgent vulnerability scan in the console to verify the application version.
After the account purchases Enterprise Edition or later, system vulnerability, application vulnerability, and urgent vulnerability scanning entitlements apply at the Enterprise Edition level even if the instance status displays an abnormal edition. No additional action is required.
Why does the vulnerability TotalCount returned by the API differ from the count in the console, or why is the first detection time later than the time when the vulnerability actually existed?
TotalCount returned by DescribeVulList is the total number of vulnerability instances across all servers, representing the combined server-by-vulnerability instances. The console displays the number of deduplicated vulnerability types, so the values can differ.
Vulnerability scans depend on the runtime state of the relevant components. If the corresponding process was not running during an earlier scan or the scan cycle had not been triggered, the vulnerability was not recorded. First detection time is when Security Center actually detected the vulnerability on the server, not its disclosure time or a retrospectively inferred time.
How do I investigate a vulnerability attack on a server that does not expose an IP address?
Immediately scan for application vulnerabilities and urgent vulnerabilities and fix them promptly.
Log on to the server and run
crontab -lto check for residual malicious scheduled tasks.Review unusual logon alerts to determine whether compromised credentials or weak passwords led to the intrusion.
Appendix
Supported operating systems for vulnerability scanning and fixing
OS Type | Version |
Windows Server |
|
CentOS |
|
Red Hat |
|
Ubuntu |
|
Alibaba Cloud Linux |
|
Anolis OS |
|
Debian |
Note Only scanning is supported; fixing is not. |
SUSE | |
Kylin | Kylin Advanced Server OS V10 |
End-of-life OS vulnerability support
For operating systems that have reached End of Life (EOL), Security Center no longer supports scanning, detection, or fixing of Linux Software Vulnerabilities and Windows System Vulnerabilities disclosed after the EOL date.
Scanning and fixing for Application Vulnerability, Emergency Vulnerability, and other Security Center features are not affected.
OS Version | Official End of Life (EOL) Date | Patch Support Cutoff Date |
Windows Server 2003 | July 14, 2015 | July 14, 2015 |
Windows Server 2008 | January 14, 2020 | January 14, 2020 |
Windows Server 2008 R2 | January 14, 2020 | January 14, 2020 |
Windows Server 2008 SP2 | January 14, 2020 | January 14, 2020 |
Windows Server 2012 | October 10, 2023 | October 10, 2023 |
Windows Server 2012 R2 | October 10, 2023 | October 10, 2023 |
Ubuntu 12.04 LTS | April 28, 2017 | April 28, 2017 |
Ubuntu 14.04 LTS | April 2019 | April 2019 |
Ubuntu 16.04 LTS | April 2021 | April 2021 |
Ubuntu 18.04 LTS | April 2023 | April 2023 |
CentOS 5 | March 31, 2017 | March 31, 2017 |
CentOS 6 | November 30, 2020 | November 30, 2020 |
CentOS 8 | December 31, 2021 | December 31, 2021 |
Red Hat 5 | March 31, 2017 | March 31, 2017 |
Red Hat 6 | November 30, 2020 | November 30, 2020 |