plamentsv / centralization-risk

Skill: CENTRALIZATION_RISK

Trigger: Protocol has privileged roles (admin, operator, governance, resource account owner)
Covers: Single points of failure, privilege escalation, external governance dependencies
Required: NO (optional -- recommended when protocol has 3+ distinct privileged roles)
Inject Into: Breadth agents

Trigger Patterns

admin|owner|operator|governance|signer_cap|SignerCapability|resource_account|
has_role|is_admin|only_admin|assert_admin|get_signer

Aptos Capability Model Context

Aptos Move uses a capability-based access control model fundamentally different from EVM modifiers:

• Signer-based: Functions receive &signer and check signer::address_of(account) == @admin
• Capability pattern: SignerCapability stored in resources grants signing rights to resource accounts
• No modifiers: Access control is enforced via assert! checks inside function bodies
• Resource accounts: Accounts controlled by SignerCapability rather than a private key
• Object ownership: Object<T> has an owner chain; ownership transfers control access

Reasoning Template

Step 1: Privilege Inventory

Enumerate ALL capability-gated functions by searching for signer checks and capability usage:

MANDATORY GREP: Search all .move files for:

• signer::address_of followed by equality checks
• SignerCapability usage (creation, storage, account::create_signer_with_capability)
• object::is_owner and ownership assertions
• Named address references (@admin, @operator, @governance, @protocol)

Categorize each by impact:

• FUND_CONTROL: Can move, lock, freeze, or destroy user funds/assets
• PARAMETER_CONTROL: Can change fees, rates, thresholds, delays
• OPERATIONAL_CONTROL: Can pause, unpause, add/remove components, whitelist/blacklist
• UPGRADE_CONTROL: Can upgrade module code (publish new version)

Step 2: Role Hierarchy and Capability Delegation

Map the capability hierarchy:

Aptos-specific checks:

• [ ] Are FUNDCONTROL and UPGRADECONTROL separated into different addresses/capabilities?
• [ ] Does any single address have both PARAMETERCONTROL and FUNDCONTROL?
• [ ] Can SignerCapability be duplicated? (if the resource containing it has copy ability -- CRITICAL)
• [ ] Can capabilities be extracted from the storing resource by anyone? (check resource field visibility)
• [ ] Is the resource account SignerCapability stored behind proper access control?

Step 3: Single Points of Failure

For each privileged role:

Severity assessment:

• Single EOA address with FUND_CONTROL -> HIGH centralization risk
• Multisig controlling admin address (off-chain, not verifiable on-chain) -> MEDIUM
• Resource account with properly guarded SignerCapability -> LOW (but document)
• Module published as immutable -> eliminates UPGRADE_CONTROL risk entirely

Aptos-specific risk: SignerCapability is the most dangerous capability -- it grants FULL control over the resource account, including publishing modules and transferring all assets. If the resource containing the capability has improper access control, it is equivalent to leaking a private key.

Step 4: External Governance Dependencies

Identify parameters or behaviors controlled by EXTERNAL governance:

Aptos-specific patterns:

• Framework governance: aptos_framework parameters controlled by Aptos governance (staking, gas, transaction limits)
• External module upgrades: Modules the protocol depends on upgrading under compatible policy -- new abort conditions, changed behavior
• Oracle operator changes: Oracle price feed operators changing configs, adding latency, pausing feeds
• Bridge governance: Wormhole guardian set changes, LayerZero oracle/relayer config

Check:

• Can external governance changes break protocol invariants?
• Does the protocol have circuit breakers for external changes?
• Are external governance timelines aligned with this protocol operational timelines?

Step 5: Emergency Powers

Document emergency/pause capabilities:

Aptos-specific checks:

• [ ] Can pausing strand user funds permanently? (resources stay in global storage but no exit path)
• [ ] Is there a maximum pause duration enforced on-chain?
• [ ] Can users exit during pause (emergency withdraw function)?
• [ ] If module is published as immutable and paused -> permanent freeze? (no upgrade possible)
• [ ] Can the freeze/blacklist mechanism on FungibleAsset be used as an emergency power?
• [ ] If no exit during pause -> apply Rule 9 (stranded asset severity floor)

Instantiation Parameters

{CONTRACTS}           -- List of modules to analyze
{ADMIN_ADDRESSES}     -- Named addresses with privileged access (@admin, @operator, etc.)
{CAPABILITY_RESOURCES} -- Resources that store SignerCapability or other capabilities
{EXTERNAL_DEPS}       -- External modules with governance dependencies

Output Schema

## Finding [CR-N]: Title

**Verdict**: CONFIRMED / PARTIAL / REFUTED
**Step Execution**: check1,2,3,4,5 | X(reason) | ?(uncertain)
**Severity**: Critical/High/Medium/Low/Info
**Location**: module::function (source_file.move:LineN)

**Centralization Type**: FUND_CONTROL / PARAMETER_CONTROL / OPERATIONAL_CONTROL / UPGRADE_CONTROL
**Affected Role**: {role_name / address / capability}
**Mitigation Present**: {multisig/timelock/immutable module/NONE}

**Description**: What is wrong
**Impact**: What can happen if role is compromised or acts maliciously
**Recommendation**: How to mitigate (add timelock module, separate capabilities, publish immutable)

Step Execution Checklist

• [ ] Step 1: ALL privileged functions enumerated (via grep for signer checks + capabilities)
• [ ] Step 2: Capability hierarchy mapped with delegation analysis
• [ ] Step 3: Single points of failure identified for each role/capability
• [ ] Step 4: External governance dependencies documented
• [ ] Step 5: Emergency powers and recovery paths assessed