Liberty91LTD Intelligence Sharing
Why Share?
Intelligence sharing creates a network effect — threats identified by one organisation protect the entire community. However, sharing must be governed, reciprocal, and risk-managed.
Sharing Models
1. ISACs (Information Sharing and Analysis Centers)
Sector-specific sharing communities.
| ISAC | Sector | URL |
|---|---|---|
| FS-ISAC | Financial Services | fs-isac.com |
| H-ISAC | Healthcare | h-isac.org |
| IT-ISAC | Technology | it-isac.org |
| E-ISAC | Energy | eisac.com |
| A-ISAC | Aviation | a-isac.com |
| Auto-ISAC | Automotive | automotiveisac.com |
Benefits: Sector-relevant intelligence, trusted community, pre-vetted members, established TLP norms.
2. FIRST (Forum of Incident Response and Security Teams)
Global incident response community. Membership-based, includes national CERTs and enterprise security teams.
Sharing via: FIRST mailing lists, TF-CSIRT community, CTI SIG.
3. MISP (Malware Information Sharing Platform)
Open-source threat intelligence platform for sharing IOCs and threat data.
How to share via MISP:
- Create an event with appropriate distribution
- Add attributes (IOCs) with correct types
- Tag with TLP, ATT&CK techniques, and galaxies
- Set distribution: Organisation only / Community / Connected communities / All
- Publish event
4. STIX/TAXII (Automated Sharing)
Standards for structured intelligence exchange.
- STIX 2.1: Format for representing intelligence (see stix-bundle skill)
- TAXII 2.1: Transport protocol for exchanging STIX bundles
TAXII channels:
- Collections: Server-hosted repositories of STIX objects
- Channels: Push-based distribution
- API roots: Discovery endpoints
5. Bilateral/Multilateral Sharing
Direct sharing with trusted partners under agreed terms.
Requirements:
- Sharing agreement (legal framework)
- TLP adherence by both parties
- Secure communication channel
- Reciprocity expectation
TLP and Sharing
| TLP | Sharing Scope | Automated Sharing? |
|---|---|---|
| RED | Named recipients only | No |
| AMBER+STRICT | Own organisation | No |
| AMBER | Organisation + need-to-know | Restricted TAXII |
| GREEN | Community | ISAC portals, MISP community |
| CLEAR | Unrestricted | Public TAXII feeds, blogs |
What to Share
Do Share
- IOCs from confirmed incidents (with context)
- TTPs observed in your environment
- Detection rules that work
- Vulnerability intelligence relevant to sector
- Anonymised incident lessons learned
Don't Share
- Source-identifying information without source consent
- Victim-identifying information without victim consent
- Raw internal telemetry or logs
- Information that reveals your security posture
- Speculation presented as intelligence
Sharing Quality
Shared intelligence should meet the same quality standards as internal products:
- Source assessment (Admiralty Scale)
- Confidence levels
- MITRE ATT&CK mapping
- Proper TLP marking
- Context (not just raw IOCs — explain what they mean)
The number one complaint about shared intelligence: "Just IOCs with no context." Always share the WHY alongside the WHAT.
Legal Considerations
- Comply with data protection regulations (GDPR, sector-specific rules)
- Ensure sharing agreements cover liability
- TLP is a trust agreement, not a legal framework — complement with contracts
- Be aware of export control regulations for certain technical intelligence
- Document all sharing decisions for audit trail