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Week 17 · Overview

Week 17 — Reflection & Review (pre-Final)

Contents6 sections

No new content. Consolidate Weeks 10–16 (with a quick callback to first-half core concepts — hashing, MACs, AES modes, key exchange, AEAD) and prepare for the final (Weeks 18–19).

Kind: Review (no lab, no flag) · Format: same skeleton as Week 7 — this repo mirrors software-security's review-week structure.

✅ This week — what to do

  1. Before class — review Weeks 10–16 (+ first-half callbacks: Wk2 hash, Wk3 MACs, Wk4 AES modes, Wk5 key exchange, Wk6 AEAD).
  2. In class (300 min) — cumulative review quiz (../../quizzes/weekly/week17-review-quiz.md) → Security Jeopardy: Champions Edition → mock final CTF/practical → debrief.
  3. Prepare — the final is Weeks 18–19: Wk18 written (cumulative, emphasis Wk10–16), Wk19 capstone practical + project demos.

Time breakdown follows the shared AGENDA.md Week 7/17 review-week block (quiz → Jeopardy → mock exam → debrief), same as software-security.

Recap — Weeks 10–16 core lesson

WkTopicKindCore lesson (one line)
10Asymmetric & Hybrid EncryptionConceptualAsymmetric crypto is too slow for bulk data — real systems wrap a fast symmetric session key (RSA-OAEP/ECDH) with public-key crypto; a fixed nonce or reused key still breaks the symmetric layer underneath (GCM two-time-pad).
11Digital Signatures & Zero-Knowledge ProofsHybridA signature proves authenticity, not uniqueness — ECDSA's (r, s) has a valid twin (r, n−s), so malleability lets an attacker mutate a signed message's identity (e.g. txid) without invalidating it; low-S normalization closes the gap.
12Secure Transport (TLS & Noise)Hybrid"The traffic is encrypted" ≠ "encrypted to the right party" — TLS's security guarantee comes from certificate validation against a trusted CA chain, not from the handshake alone; skip verification and MITM is trivial.
13End-to-End EncryptionHybridTransport encryption (TLS) protects data in transit but the server is still a trusted third party that can read plaintext at rest/in processing; true E2EE (client-side hybrid encryption) removes the server from the trust boundary entirely.
14User AuthenticationHybridSending a password over TLS still hands the plaintext to the server — a challenge-response/PAKE-style protocol proves knowledge of a secret without ever transmitting it, closing a gap TLS alone does not.
15Post-Quantum CryptographyLabQuantum computers (Shor) break RSA/ECC outright but only dent AES/SHA (Grover) — hash-based one-time signatures (Lamport) are quantum-resistant only if the key is used exactly once; reuse leaks enough private-key bits to forge a second signature.
16Capstone Studio—Putting the whole term together: threat-model your own build, show the attack, show the fix, and defend the design choices live — the same "attack → root cause → fix" arc as every weekly lab, now end-to-end on your own project.

First-half callback (Wk2–6): unsalted hashing is crackable (Wk2) → a MAC must be purpose-built, not hash(secret+data) (Wk3, length-extension) → encryption without integrity is malleable (Wk4, CBC bit-flip) → an unauthenticated key exchange is MITM-able (Wk5) → combining confidentiality + integrity correctly is AEAD, and doing it naively leaks a padding oracle (Wk6). The Wk10–15 arc is the asymmetric/protocol-layer sequel to that symmetric-primitives arc.

🎯 Signature activity — "Security Jeopardy: Champions Edition"

Whole-course quiz-show format (mirrors software-security Week 17), categories built from the table above:

CategorySpans
Asymmetric & HybridWk10
Signatures & ZKPWk11
Transport & TLSWk12
E2EEWk13
AuthenticationWk14
PQCWk15
First-Half CallbackWk2–6 (wildcard row, higher point values)
  • Teams answer in Jeopardy point tiers (100/200/300/400/500 — higher value = harder/more applied question, e.g. "explain why" vs. "define").
  • Instructor-run; question bank not yet built — add it as ../../instructor/week17-jeopardy-bank.md (git-ignored, mirroring the answer-key convention) when this week is staffed.
  • Scores feed the same season-long Houses/XP leaderboard as every other week.

🧪 Mock final prep

  • Format: dry-run of the exact Week 19 practical format — mixed asymmetric/signature/ transport/E2EE/auth/PQC challenges, teams, sandbox targets only, ungraded (participation).
  • Targets: reuse this term's built labs — labs/week10-hybrid-encryption (audit-the-AI nonce-reuse), labs/week11-signatures-zkp (ECDSA malleability), labs/week12-secure-transport (cert-bypass MITM), labs/week13-e2e-encryption (TLS-vs-E2EE server-log evidence), labs/week14-authentication (password-over-the-wire vs. challenge-response), labs/week15-pqc (Lamport key-reuse forgery) — plus a callback item from Wk2–6.
  • Walkthrough: a dedicated mock-ctf.md (with hints + self-check pointers, no flags) mirrors software-security/labs/week17-review-final-prep/mock-ctf.md's table format (challenge / topic / hint / self-check): six post-midterm challenges (Wk10–15) plus a first-half callback round (Wk2–6).

Exam-prep note

The final is cumulative (Wk1–16) but emphasizes Weeks 10–16, matching the sibling software-security course's Wk17/Wk18 pattern (course-plan-19weeks.md: "Week 18 — Written exam: cumulative, with emphasis on Weeks 10–16"). Concretely:

  • Wk18 written exam item bank should weight roughly 60–70% Wk10–16 content, 30–40% Wk1–6 + review-week callbacks.
  • Wk19 capstone practical draws its challenges primarily from Wk10–16's lab arc (see targets above), plus one first-half callback challenge, same ratio as the mock above.

Covers

Weeks 10–16: hybrid encryption, signatures & ZKP, secure transport, E2E encryption, authentication, PQC, capstone studio (Wk16 — no separate lab dir by design, see project/README.md).

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