A security alert is a structured, prioritised mechanism designed to signal an active threat in real time, a vulnerability A critical event or incident in progress that compromises the security of a system, network, organisation or critical infrastructure. Issued by automated systems (e.g. : SIEMIDS/IPS) or certified authorities (ANSSICISA, CERT-FR...), it aims to trigger a rapid and coordinated response to mitigate risks and protect digital assets.
Essential features
- Proactive detection :
- Standardised structuring :
- Use of formats such as STIX/TAXII to share threat data in an interoperable way.
- Severity scores (e.g. : CVSS for vulnerabilities) to prioritise actions.
- Communication channels :
- Distribution via dedicated platforms (e.g. MISP), encrypted emails, notifications in dashboards (e.g. Splunk), or emergency messages (SMS, calls).
Key components of an effective alert
| Element | Description | Examples |
|---|---|---|
| Contextualisation | Details of the threat: origin, targets, techniques (MITRE ATT&CK), impact. | Exploitation of CVE-2023-1234 via a ransomware targeting hospitals. |
| Recommendations | Practical steps: patches, network segment isolation, reset. | Apply the Microsoft MS12-020 patch to counter EternalBlue. |
| Criticality levels | Prioritisation according to urgency and impact: critical, high, medium, low. | Critical: Remote code execution (RCE). Low: Display vulnerability. |
| Designated managers | Teams or roles in charge of the response (SOCinternal CERT, CISO). | The SOC analyses and the network team isolates the affected servers. |
Players and ecosystem
Authorities and bodies
- France :
- ANSSI Critical advisories: publishes critical advisories (e.g. state vulnerabilities) and provides guidance to critical operators.
- CERT-FR Distributes technical bulletins (e.g. ransomware attacks).
- International :
- CISA (United States) Alert on transnational threats (e.g. Russian APT29 campaigns).
- INTERPOL Cybercrime Directorate Coordinates global responses (e.g. taking charge of botnets).
- Private sector :
- Microsoft Security Response Center (MSRC) Exchange Server: reports flaws in its products (e.g. Exchange Server).
- Corporate CERTs Manage internal incidents (e.g. data leaks at Orange Cyberdefense).
Alert life cycle
- Detection Monitoring via tools (EDRlogs).
- Validation Elimination of false positives (e.g. atypical legitimate activity).
- Prioritisation : CVSS score β₯ 7.0 β critical emergency.
- Broadcast Communication to stakeholders via secure channels.
- Response Corrective action, isolation, investigation forensics.
- Post-mortem Retrospective analysis and process improvement.
Examples and trends
- Log4Shell (2021) Global alert on vulnerability CVE-2021-44228 in Log4j, rated 10/10 in CVSS. The ANSSI has requested patches for French administrations within 24 hours.
- Supply Chain Attacks ENISA alert on compromised open source libraries (e.g. SolarWinds).
- Ransomware LockBit CERT-FR has issued mitigation guides following attacks on French SMEs in 2023.
Good Practices
- Automation :
- Integrating playbooks SOAR (e.g. Palo Alto Cortex XSOAR) to automate responses (IP blocking, file quarantine).
- Continuing education :
- Collaboration :
- Participate in ISAC (Information Sharing and Analysis Centers) to exchange sector-specific threat data.
- Compliance with legal frameworks :
- Compliance with RGPD (notification within 72 hours in the event of data leakage) or the NIS2 in the EU.
π Key figures
- World :
- 68% of organisations suffer unaddressed alerts due to a lack of resources (IBM Cost of a Data Breach 2023).
- Unpatched vulnerabilities account for 60% of data breaches (Verizon DBIR).
- France :
- 45% of French companies activated a response plan following a major alert in 2022 (ANSSI).
- The average response time to an alert is 12 hours in large companies, compared with 72 hours in SMEs (CESIN).
