Threat › Module 6 › Lesson 3
Feed Quality
Feed quality literacy — confidence, timeliness, false-positive rate, overlap, lifecycle — score rows on `$TI_LAB` sample IOC stubs.
Visual · t33_feed_quality
Feed quality = named scoring rows. $TI_LAB. Original Cyberlium.
Opening
Bad feeds burn SOC hours — name quality dimensions on YOUR lab stubs before auto-blocking prod on unvetted indicators.
Feed quality literacy names: confidence/tlp handling category, timeliness/freshness category, false-positive rate literacy stub, overlap/duplication with other feeds category, IOC lifecycle (active/expired) category, and source reputation tier stub. Analyst scores three sample indicators from `$TI_LAB` instructor stub — documents quality scorecard per row with disposition (monitor, block lab only, expire) — without auto-blocking employer prod on unvalidated IOCs, without treating low-confidence paste as critical, without quality theater on marketplace leaks. Cyberlium links Module 3 IOC literacy to feed consumption discipline. Refused: prod block without validation, marketplace IOC quality bypass, hide false-positive rate. Lab row: feed quality scorecard three IOC rows with disposition stub.
1. Quality dimensions
Confidence, timeliness, false-positive rate, overlap, lifecycle — five scoring anchors.
Each dimension gets a stub score on YOUR lab sample IOC rows.
Command guide
Try these commands — Quality dimensions
═══ TOOLS & WEBSITES ═══ Browse / read these (authorized learning only — stay in YOUR lab / program scope)
FIRST TI metrics — https://www.first.org/ CISA — https://www.cisa.gov/ MISP — https://www.misp-project.org/
═══ INSTALL ═══
Linux (Debian/Ubuntu):
Command — copy this
sudo apt install python3
macOS:
Command — copy this
brew install python3
Windows: Download https://python.org/downloads/
═══ LINUX / macOS ═══
Command — copy this
export TI_LAB=${TI_LAB:-$HOME/cyberlium-lab/t33-ti}
cat > "$TI_LAB/feeds/feed-quality-checklist.md" <<'EOF'
# Feed Quality Checklist — YOUR SOC ingestion
- [ ] Source reputation documented (vendor, ISAC, gov advisory)
- [ ] Confidence score assigned per indicator
- [ ] TTL / expiration policy defined (stale IOC retirement)
- [ ] False positive rate tracked after SIEM deployment
- [ ] Deduplication against existing IOC store
- [ ] Context: ATT&CK technique tagged, not raw IP list only
- [ ] Legal: sharing agreement / contract covers use case
- [ ] No automatic block on critical infra without review
Review YOUR feed policy — never ingest criminal marketplace dumps
EOFCommand — copy this
grep '\[ \]' "$TI_LAB/feeds/feed-quality-checklist.md"
python3 -c "print('Feed quality: reputation + TTL + confidence + ATT&CK context')"Primary tools to practice this lesson: grep, python3. Reference sites: FIRST TI metrics (https://www.first.org/); CISA (https://www.cisa.gov/); MISP (https://www.misp-project.org/). Run every command in the box — install first, then the usage lines — only on YOUR lab / program scope.
2. Disposition discipline
Monitor vs block lab vs expire — document decision per stub IOC.
Link TLP/confidence to Module 8 collection hygiene preview row.
3. Refused
No prod auto-block on unvalidated feed IOCs; no marketplace leak quality bypass.
Quality literacy supports SOC triage — not blind blocking.
4. What you ship: feed quality scorecard
Three IOC rows + five dimension stubs + disposition + NEVER prod auto-block line.
5. What you record before the next lesson
Feed quality scorecard path.
6. Wrong vs right: criminal markets vs YOUR lab IOCs
Worked failure — same MSF word, opposite target. Right never needs a café Wi-Fi or classmate laptop.
Wrong
Push unvalidated paste-bin IOCs to employer prod firewall block list as 'feed quality test.'
Right
Feed quality scorecard from `$TI_LAB` sample IOCs. Next: Feeds Lab.
Mission: feed quality scorecard
1) Name five quality dimensions. 2) Score three lab stub IOCs. 3) Disposition per row UTC. 4) Write NEVER prod auto-block without validation line.
Stuck? Ask Cyberlium AI Mentor
Ask Mentor: “IOC lifecycle expire — literacy default?”
Knowledge Check
APPLY: Feed quality literacy uses:
Multiple choice
Knowledge Check
APPLY: True or False: Low-confidence paste IOCs deserve prod block default.
True or False
Knowledge Check
APPLY: Quality dimensions include:
Multiple choice