YanoSec
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Course / 10 Crypto and files / Lesson 15 of 19

What OSINT is

Estimated time: 15 min reading · 15 min activity

Open-source intelligence, OSINT, uses accessible information to answer a defined question. Accessible information may be public, but public availability is different from permission to investigate a person. In this module all work stays inside the supplied fictional Night Desk corpus, the complete set of records permitted for the activity.

A source is the record from which you take a claim. Verification checks whether that claim is supported, rather than merely repeating it. Corroboration means additional relevant support. Two records agreeing can strengthen a conclusion, but copied claims are not independent just because they appear in different places.

Before you begin

Estimated time
15 min reading, 15 min activity. Setup and optional practice may take longer.
Where you work
Use only the supplied fictional corpus: notices, source cards, saved page, image description/map and DNS/registration table. Keep work in private notes. No real-person research, live search, image upload, map lookup, contact or account is required or authorized by this exercise.
Without a lab
All evidence needed for the activity appears on this page. Copy it into notes if downloads are unavailable. Read the labeled model and predict each result; a paper trace practises the reasoning while tool operation waits for a lab. Reading needs no JavaScript. Answer checking needs JavaScript and a secure context; saving progress also needs usable browser storage.

After this lesson you can:

  • Cite two fictional notices that state the same cable fact.
  • Keep a single opening-time sentence separate from that corroborated fact.
  • Leave the live web and any real person outside this checkpoint.

01Example

Fresh fictional worked comparison; the packet’s notices are separate activity evidence.

Record W1: the blue cabinet holds the key.
Record W2: copied verbatim from W1.
Observation: two records agree.
Limit: W2 is a copy, so it is not independent verification.
Next need: another relevant source with a separately understood origin.

02A claim needs a second source inside the packet

Read each notice as a claim with a source label and story posting date. Agreement does not prove truth; disagreement does not justify choosing whichever time is convenient. Note whether records share an origin, whether one is newer, and what further evidence would be needed.

N3 and N4 give the same drawer location, but the packet does not establish independent acquisition or an external check. Describe them as two agreeing notices. The record supports what the notices say; it does not establish the physical world outside this fiction.

Support a narrow research statement with cited fictional records and make uncertainty visible.Model. A teaching model drawn by hand. It shows the idea, not real tool output.

Read the full explanation below.

The two supplied records agreeW2 independently verifies W1

Record W1

Record W1: the blue cabinet holds the key.
Selected evidence · W1 supplied origin

Record W2

Record W2: copied verbatim from W1.
Selected evidence · W2 copy
supported

The two supplied records agree

W2 repeats W1.

Agreement does not imply independent verification.

W1 supplied origin

W2 copy ← W1 supplied origin

W2 repeats W1. Agreement does not imply independent verification.

Follow the explanation

  1. W2 repeats W1. Agreement does not imply independent verification.
  2. The supplied origin explicitly derives W2 from W1. Another relevant source with separately understood origin is still needed.
Read every state and value

1. W2 repeats W1. Agreement does not imply independent verification.

Evidence selected
Record W1 · Record W2
Current claim
agreement
Source origins
W1 supplied origin · W2 copy

2. The supplied origin explicitly derives W2 from W1. Another relevant source with separately understood origin is still needed.

Evidence selected
Record W1 · Record W2
Current claim
independent
Source origins
W1 supplied origin · W2 copy
Agreement among copied records does not supply independent verification.

03Write the drawer the two cable notices share

Read N3 and N4 for the guided question about the spare cable. Then compare the other pair as a separate conflict.

<!DOCTYPE html>
<html lang="en">
<head><meta charset="utf-8"><title>Night Desk notices, fictional</title></head>
<body>
<p>Original fictional packet. These notices are not a real club board.</p>
<article id="n1"><h1>Notice N1</h1><p>Room Lamp opens at 09:00. Posted 2026-03-01 in the story.</p></article>
<article id="n2"><h1>Notice N2</h1><p>Room Lamp opens at 09:30. Posted 2026-03-02 in the story.</p></article>
<article id="n3"><h1>Notice N3</h1><p>The spare cable is in drawer 2. Posted 2026-03-03 in the story.</p></article>
<article id="n4"><h1>Notice N4</h1><p>The spare cable is in drawer 2. Posted 2026-03-04 in the story.</p></article>
</body>
</html>

Download the fictional notices

Label: how to cite the fictional notices.
N3 and N4 both say the spare cable is in drawer 2. Two notices in this packet support that sentence.
N1 says 09:00. N2 says 09:30. Those two sentences disagree.
One notice states a claim. Two agreeing notices are additional support, but this packet does not establish their independent acquisition or truth. Copies of one claim would not be independent verification.
No real bulletin board was visited.

Download the citation note

  1. Copy the drawer sentence from N3 and N4, naming both notice IDs as sources. Both place the cable in drawer 2.
  2. Read N1 and N2. Record 09:00 versus 09:30 as a disagreement about opening time, without resolving it by assumption.
  3. Write one conclusion with its limit: the packet has two agreeing drawer notices, but their independence and truth are not separately established.
  4. Stop at those cited statements. Do not look for a real club, room or person to complete the fictional case.

04Optional challenge

For about ten optional minutes, draft a follow-up research question about the conflicting room times. Name the missing evidence, such as a current authoritative schedule with an understood source, and keep it as a note. No contact or live research is part of this activity.

05Fresh cases for the checks

Use these fictional cases for the checks below. They have different inputs from the worked examples. Read them here or make notes; no installation or external service is needed.

Notice card A: fresh fictional packetOwned fixture. An original file made for this course. Follow the activity's instructions in your own lab.

M1: the spare adapter is in cupboard 4. Origin: the fictional stock register.
M2: the spare adapter is in cupboard 4. Origin: copied verbatim from M1.
M3: the spare adapter is in cupboard 4. Origin: a separately maintained fictional inventory check, not copied from M1 or M2.
M4: the reading room opens at 08:40. Origin: one fictional notice; no other opening-time source is supplied.
The packet describes source independence in the fiction; it does not establish an external physical event.

Conflict card B: separate fictional timesOwned fixture. An original file made for this course. Follow the activity's instructions in your own lab.

Notice V1, dated 2026-07-01, says a room opens at 08:00.
Notice V2, dated 2026-07-02, says it opens at 08:30.
No current authoritative schedule or change notice is supplied. No live lookup is permitted.

06Explain the evidence and its limit

Optional self-check: write claim → source → agreement/conflict → origin relationship → limit for a notice pair.

Review it: distinguish copies from independent support, keep unrelated claims separate, and leave external truth and unresolved questions within the fictional packet boundary.

07Common mistakes

If two copies are called independent sources, inspect their origin. Separate matching text from independent acquisition.

If the latest notice is automatically called true, state what evidence makes it authoritative; a date alone cannot settle that.

If the story turns into research on a real person, stop and return to the supplied corpus.

References

  • NIST SP 800-115

    Testing-planning background on defining objectives, scope and handling evidence. The notices are original fiction.