Oracle Analysis

ORACLE_ANALYSIS Skill (Sui)

Trigger Pattern: ORACLE flag (required) Inject Into: Breadth agents, depth-external, depth-edge-case Purpose: Analyze oracle integrations in Sui Move protocols for staleness, decimal handling, failure modes, and manipulation vectors

For every oracle the protocol consumes:

STEP PRIORITY: Steps 6 (Failure Modes) and 5c (Deviation Reference) are where HIGH/CRITICAL severity findings most commonly hide. Do NOT rush these steps. If constrained, skip conditional sections (4a-4d, 5a) before skipping 5c or 6.

1. Oracle Inventory

Enumerate ALL oracle data sources the protocol reads:

For each oracle: What decision does the protocol make based on this data? (pricing, liquidation threshold, reward rate, share price, swap amount, etc.)

Hardcoded stablecoin pricing: Does the protocol skip oracle lookup for any asset and hardcode its price (e.g., USDC = 1e8)? All assets require dynamic oracle pricing — stablecoins depeg.

Sui-specific inventory checks:

• Is the oracle data passed as a shared object parameter (&PriceInfoObject) or read from on-chain state?
• Does the protocol use pyth::price_info::get_price_info_from_price_info_object() or a wrapper?
• Are oracle objects passed by reference (&) or by mutable reference (&mut)?
• Shared object contention: Oracle objects like Pyth's PriceInfoObject are shared objects. During high-volatility periods, multiple transactions compete to read/update the same oracle object, causing transaction ordering dependencies and potential stale reads due to sequencing delays.

2. Staleness Analysis

For each oracle identified in Step 1:

2a. Staleness Checks Present?

Chained feed deviation: If derived prices require multiple feeds (e.g., token_A/USD via token_A/SUI + SUI/USD), sum individual deviation thresholds to compute total worst-case deviation. If total exceeds LTV buffer → FINDING.

CRITICAL -- Sui uses MILLISECONDS: clock::timestamp_ms(clock) returns milliseconds, not seconds. Pyth's price.timestamp returns seconds. If the protocol compares these without unit conversion, the staleness check is 1000x too lenient or too strict. Check for:

• publish_time (seconds from Pyth) vs clock::timestamp_ms() (milliseconds) -- MUST convert one to match the other
• Direct subtraction without unit normalization
• Constants like MAX_STALENESS -- is the value in seconds or milliseconds?

Correct Sui staleness pattern:

// Pyth on Sui -- check price freshness
let price = pyth::price_info::get_price_info_from_price_info_object(price_info_object);
let price_data = price_info::get_price_feed(&price);
let current_price = price_feed::get_price(price_data);
let timestamp = price::get_timestamp(&current_price); // SECONDS
let now_ms = clock::timestamp_ms(clock); // MILLISECONDS -- Clock is shared object at 0x6
let now_s = now_ms / 1000; // Convert to seconds to match Pyth
assert!(now_s - timestamp <= MAX_STALENESS_SECONDS, E_STALE_PRICE);

If NO staleness check: What happens when the oracle returns stale data?

• Protocol uses stale price for liquidations -- unfair liquidations
• Protocol uses stale price for minting/deposits -- mispriced assets
• Protocol uses stale price for swaps -- arbitrage opportunity
• Protocol uses stale price for rewards -- incorrect distribution

2b. Stale Data Impact Trace

For each consumer function, trace the impact of receiving data that is {heartbeat x 2} old:

2c. Pyth-Specific Checks

2d. Switchboard V2-Specific Checks

2e. Supra-Specific Checks

3. Decimal Normalization Audit

For each oracle data flow:

Pyth exponent handling: Pyth returns Price { price: i64, conf: u64, expo: i32, timestamp: u64 }. The expo field is typically negative (e.g., -8 means price has 8 decimal places). Verify:

• Is expo read dynamically or assumed to be a fixed value?
• Is the sign of expo handled correctly (negative exponent = division, positive = multiplication)?
• Does 10^|expo| computation overflow for large exponents?

MANDATORY GREP: Search all oracle consumer modules for hardcoded decimal constants: 1_000_000_000, 100_000_000, 1_000_000, 10_000, 1e8, 1e6, 1e9, DECIMAL, PRECISION. For each hit: (1) Is this a decimal normalization constant? (2) Does it match the ACTUAL oracle's exponent? (3) If the oracle feed changes exponent, does this constant break?

Decimal chain trace: For each arithmetic operation using oracle data, trace the full decimal chain: oracle_output_decimals -> normalization_step -> consumer_expected_decimals. If any step uses a hardcoded constant rather than reading the exponent dynamically -> FINDING.

Common Sui decimal mismatches:

• Pyth price expo = -8, but protocol assumes -18 (or vice versa)
• SUI has 9 decimals (MIST_PER_SUI = 1_000_000_000)
• USDC on Sui has 6 decimals
• Cross-multiplication without normalization: price * amount where price and amount have different decimal bases

3d. Decimal Grep Sweep (MECHANICAL -- MANDATORY)

Grep ALL oracle consumer modules for 10_|decimals|PRECISION|SCALE|expo|pow. For each match, fill:

If ANY row shows Match=NO or oracle decimals UNKNOWN with hardcoded constant -> FINDING (R16). Skipping this step is a Step Execution violation (x3d).

4. TWAP-Specific Analysis

If protocol uses any TWAP oracle (on-chain pool observation, custom TWAP accumulator, etc.):

4a. TWAP Window Analysis

Rule of thumb: TWAP window < 30 min AND pool TVL < $10M -> potentially manipulable. Sui-specific: On Sui, TWAP typically relies on CLOB or AMM observation points. Check if the TWAP source is a CLOB (orderbook DEX) or AMM. CLOB TWAPs can be manipulated with limit orders that are never filled.

4b. TWAP Arithmetic

4c. TWAP Lagging Behavior

During rapid price movements, TWAP lags spot price. Trace:

• What happens when TWAP price is significantly lower than spot? (discounted minting/borrowing)
• What happens when TWAP price is significantly higher than spot? (premium liquidations)
• Is this lag exploitable by attackers who can predict the direction?

4d. TWAP Cold-Start Analysis

Check oracle behavior when history is insufficient: (1) zero snapshots, (2) single snapshot, (3) window period not yet elapsed.

For each exploitable state: can attacker act during cold-start window at manipulated price? Tag: [BOUNDARY:snapshots=0], [BOUNDARY:snapshots=1]. If TWAP returns 0 or aborts during cold-start with no fallback -> FINDING (R16, minimum Medium).

5. Oracle Weight / Threshold Boundaries

For multi-oracle systems or oracle-based thresholds:

5a. Multi-Oracle Systems

Check: What happens at exact threshold boundaries?

• If median of [100, 100, 101]: result = 100. Is that correct?
• If weighted average with equal weights rounds down: impact?
• If one oracle aborts: does fallback handle it gracefully?

5b. Oracle-Based Thresholds

Check > vs >=: At the exact threshold value, does the protocol behave as intended?

5c. Deviation Reference Point Audit

For each deviation check in the protocol (max_deviation, price_deviation, deviation_threshold, etc.):

Checks:

1. What is the deviation MEASURED AGAINST? (previous on-chain price, TWAP, external oracle, hardcoded value)
2. Is the reference point itself manipulable? (e.g., if deviation checks current vs last-recorded, and last-recorded is admin-settable -> admin can set a stale reference that makes all future prices "within deviation")
3. Can the reference become stale? (e.g., if reference is updated only on specific actions, and those actions stop occurring)
4. Is the first recorded price special? (no prior reference -> deviation check may be bypassed on first update) Tag: [TRACE:deviation check: current vs {reference} -> reference source: {X} -> manipulable: {Y/N}]

6. Oracle Failure Modes

For each oracle, model failure scenarios:

Sui-specific failure: Pyth on Sui requires explicit price update transactions (pyth::update_price_feeds). If the protocol does not enforce fresh updates before reading, prices can be arbitrarily stale. Check:

• Does the protocol call update_price_feeds in the same PTB before reading?
• Or does it rely on external keepers to update? If so, what if keepers stop?
• Does the protocol use get_price_no_older_than() which enforces freshness?

For each unmitigated failure mode: What is the worst-case impact? Can it lead to fund loss?

Circuit breaker check: Does the protocol have a mechanism to pause oracle-dependent operations if the oracle enters a failure state?

Finding Template

**ID**: [OR-N]
**Severity**: [based on fund impact and likelihood of oracle failure/manipulation]
**Step Execution**: check1,2,3,4,5,6 | x(reasons) | ?(uncertain)
**Rules Applied**: [R1:check, R4:check, R10:check, R16:check]
**Location**: module::function:LineN
**Title**: Oracle [issue type] in [function] enables [attack/failure]
**Description**: [Specific oracle issue with data flow trace]
**Impact**: [Quantified impact under worst-case oracle scenario]

Instantiation Parameters

{CONTRACTS}           -- Move modules to analyze
{ORACLE_MODULES}      -- Oracle integration modules (pyth, supra, custom)
{PRICE_OBJECTS}       -- Shared oracle objects (PriceInfoObject, etc.)
{CONSUMER_FUNCTIONS}  -- Functions that read oracle data
{ORACLE_TYPE}         -- Pyth / Supra / Switchboard / Custom
{HEARTBEAT}           -- Expected update frequency

Output Schema

Step Execution Checklist (MANDATORY)