Flagportation
Name: - Category: - Difficulty: Raw flag is stored in
Scenario
Flagportation attack path
Name: - Category: - Difficulty: Raw proof is stored in
Objective
Challenge walkthrough focused on Quantum evidence, validation, and reusable operator lessons.
Walkthrough flow
Circuit constraints
State manipulation
Measurement strategy
Proof captured
Source coverage
Moderate source coverage
Status: partial. This article is generated from 5 sanitized Markdown sources and keeps raw flags, credentials, keys, cookies, and reusable secrets out of the rendered blog.
Moderate confidence: the page is useful for review, but it should be treated as partial because the available source material is thinner or less narrative-complete.
- Quantum/Flagportation/writeup.md
- htb-challenge/Quantum/Flagportation/notes.md
- htb-challenge/Quantum/Flagportation/memory-summary.md
- htb-challenge/Quantum/Flagportation/hypothesis-board.md
- HTB/_knowledge/exports/ctf-lightrag-latest-203412/documents/challenge__Quantum__Flagportation__notes.md.388adaf3b7.md
Technical Walkthrough
Writeup
Challenge
- Name:
- Category:
- Difficulty:
Summary
Artifact Inventory
Analysis
Solve
Flag
Raw flag is stored in loot/flag.txt.
Lessons
Source-Backed Dossier
The sections below are merged from companion Markdown notes for the same case. They are rendered after sanitization so the article stays precise without publishing raw flags, credentials, or target-specific secrets.
Notes
Scope
- Challenge: Flagportation
- Category: Quantum
- Difficulty: Very Easy
- Target: <TARGET>:32294
- Started: 2026-05-07
Evidence Ledger
| Timestamp | Action | Finding | Next |
|---|---|---|---|
| 00:00 | Read server.py | Quantum teleportation protocol, 204 qubits (51 bytes), flag encoded as bit pairs | Write solver |
| 00:02 | Debug banner | 204 qubits, first prompt includes qubit data | Fix parsing |
| 00:03 | Run solve.py | All 204 qubits decoded, flag recovered | Done |
Vulnerability
Standard quantum teleportation protocol — no authentication required.
Encoding: flag bytes → bit pairs → qubit states
- "00" → |0⟩ (Z basis), "01" → |1⟩ (Z basis)
- "10" → |+⟩ (X basis), "11" → |-⟩ (X basis)
Correction gates based on Alice's measurements (q0, q1):
- q0=0, q1=0: identity (H;H cancels)
- q0=0, q1=1: X gate on q2
- q0=1, q1=0: Z gate on q2
- q0=1, q1=1: Z then X on q2
Decoding: measure q2 in the given basis, map result to bit pair.
| 2026-05-27T23:35:17Z | backfill | challenge-state.json | Legacy workspace backfilled with deterministic state | High | Validate before further work |
Memory Summary
Metadata
- Platform: HackTheBox Challenges
- Category:
- Challenge:
- Difficulty:
- Source workspace:
Validated Solve Chain
Concepts only. Do not include raw flags, reusable credentials, tokens, cookies, private keys, or live secrets.
1.
Reusable Lessons
-
Dead Ends
-
Tool Quirks
-
Evidence Paths
-
Ingestion Decision
- Proposed for LightRAG: yes/no
- Requires user approval before ingestion: yes
Hypothesis Board
| Rank | Path | Evidence | Missing Proof | Cheapest Validation | Confidence | Status |
|---|
Closed Branches
| Branch | Evidence Tested | Failure Output | Reason Closed | Revisit Condition |
|---|
Notes
Scope
- Challenge: Flagportation
- Category: Quantum
- Difficulty: Very Easy
- Target: <TARGET>:32294
- Started: 2026-05-07
Evidence Ledger
| Timestamp | Action | Finding | Next |
|---|---|---|---|
| 00: <REDACTED>, 204 qubits (51 bytes), flag encoded as bit pairs | Write solver | ||
| 00:02 | Debug banner | 204 qubits, first prompt includes qubit data | Fix parsing |
| 00: <REDACTED>, flag recovered | Done |
Vulnerability
Standard quantum teleportation protocol — no authentication required.
Encoding: <REDACTED>
- "00" → |0⟩ (Z basis), "01" → |1⟩ (Z basis)
- "10" → |+⟩ (X basis), "11" → |-⟩ (X basis)
Correction gates based on Alice's measurements (q0, q1):
- q0=0, q1=0: identity (H;H cancels)
- q0=0, q1=1: X gate on q2
- q0=1, q1=0: Z gate on q2
- q0=1, q1=1: Z then X on q2
Decoding: measure q2 in the given basis, map result to bit pair.
| 2026-05-27T23:35:17Z | backfill | challenge-state.json | Legacy workspace backfilled with deterministic state | High | Validate before further work |
Technical analogy
How to remember this solve
Think of the quantum circuit like a fragile sequence of switches. The solve is about arranging the switches so the final measurement lands in the one state that unlocks the flag.
For Flagportation, keep the mental model simple: identify the trusted assumption, prove it with the smallest safe test, then automate or repeat only the part that directly leads to the flag.