Hypotheses
Hypothesis literacy — observed facts, inference, and testable statements from $DFIR_LAB timeline work.
Visual · t26_hypotheses
Hypotheses = testable inference from evidence. $DFIR_LAB. Original Cyberlium.
State what you think happened — and what would prove you wrong — before you write a report strangers will trust.
Hypothesis literacy separates observed facts (log line, hash match, PCAP five-tuple) from inferences (user likely opened attachment) from hypotheses (initial access via phishing — test by mail log + file path correlation). Each hypothesis row: statement, supporting artifacts, falsification test, confidence, status (open/closed). Cyberlium on $DFIR_LAB practice cases — NOT presenting hypothesis as court conclusion, NOT single-artifact certainty, NOT hypotheses built from planted evidence. Legal reporting Module 8 requires observed/inferred/hypothesis sections distinct. Refused: 'attacker nation-state X' without evidence class, unauthorized attribution drama. Lab: three hypotheses with falsification tests tied to Module 7-2 correlation rows.
1. Three layers
Observed: directly logged or imaged. Inferred: reasonable single-step conclusion. Hypothesis: testable story needing multiple artifacts.
Report language must not collapse layers — ethics and legal risk if you do.
Command guide
Try these commands — Three layers
═══ TOOLS & WEBSITES ═══ Browse / read these (authorized learning only — stay in YOUR lab / program scope)
Timeline + hex — https://www.sleuthkit.org/ (artifact timestamp context) Autopsy — https://www.autopsy.com/ (timeline + file metadata) RFC 3227 — https://www.rfc-editor.org/rfc/rfc3227
═══ INSTALL ═══
Linux (Debian/Ubuntu): Built-in (vim-common / xxd)
macOS: Built-in
Windows: Use WSL or Git Bash xxd
═══ LINUX / macOS ═══
Command — copy this
export LAB_DFIR=${LAB_DFIR:-$HOME/cyberlium-lab/t26-dfir}
grep '2026-08-22' "$LAB_DFIR/notes/timeline.csv" | grep -v timestamp
grep 'Failed password' "$LAB_DFIR/notes/fake-log-lines.txt" | head -2
xxd "$LAB_DFIR/evidence/sample.bin" | head -3Primary tools to practice this lesson: grep, xxd. Reference sites: Timeline + hex (https://www.sleuthkit.org/); Autopsy (https://www.autopsy.com/); RFC 3227 (https://www.rfc-editor.org/rfc/rfc3227). Run every command in the box — install first, then the usage lines — only on YOUR lab / program scope.
2. Falsification tests
Each hypothesis lists what evidence would disprove it — scientific discipline in DFIR.
Open hypotheses OK in lab report with gap note — not hidden as certainty.
3. Scope refuse
No hypotheses from unauthorized acquisitions; no planted artifacts to confirm bias.
Attribution beyond evidence class refused — stick to artifact-backed statements.
4. What you ship: hypothesis row template
Observed/inferred/hypothesis definitions + row fields + three lab hypotheses with falsification tests.
5. What you record before the next lesson
Hypothesis row template path.
6. Wrong vs right: tampering evidence vs chain of custody
Worked failure — same MSF word, opposite target. Right never needs a café Wi-Fi or classmate laptop.
- Wrong: Write 'confirmed APT29' from one suspicious IP with no evidence class.
- Right: Hypothesis template with falsification tests on $DFIR_LAB. Next: Timeline Lab.
Mission: hypothesis row template
1) Define observed inferred hypothesis. 2) List row fields including falsification test. 3) Three lab hypotheses linked to correlation rows. 4) Write NEVER collapse layers in report.
Stuck? Ask Cyberlium AI Mentor
Ask Mentor: “Open hypothesis — how in executive summary?”
APPLY: Hypothesis row includes:
APPLY: True or False: Single artifact proves nation-state attribution.
APPLY: Observed vs inferred in report: