plamentsv / account-lifecycle

ACCOUNT_LIFECYCLE Skill

Trigger Pattern: ACCOUNT_CLOSING flag detected (close/CloseAccount usage)
Inject Into: Breadth agents, depth agents
Finding prefix: [AL-N]
Rules referenced: S4, R9

For every account close operation in the Solana program:

1. Close Operation Inventory

List all account closing operations:

2. Close Completeness

For each close operation, verify ALL steps:

Anchor close: Handles all 4 steps automatically. Manual closing MUST do all 4.
Missing step impact:

• Data not zeroed → residual data readable by other programs
• Lamports not fully transferred → rent-exempt lamports stranded (Rule 9)
• Discriminator not set → account can be "reopened" with stale type
• Owner not transferred → program still has authority over closed account

3. Revival Attack Analysis (S4 - CRITICAL)

For each close operation:

Attack (S4): Within the SAME transaction, after an account is closed (lamports drained, data zeroed):

1. Close account (lamports go to attacker)
2. In same tx, re-fund account with lamports (becomes rent-exempt again)
3. Account data is all zeros but account exists again
4. Next instruction that checks account.data_len() > 0 or assumes "closed accounts don't exist" fails

Defense: Set discriminator to a CLOSED sentinel value. Check discriminator on every access, not just data length.

4. Rent Recovery

For each close operation:

Check: Are ALL lamports transferred? Partial transfer leaves lamports stranded.

5. Token Account Closure

For each SPL Token account closure:

SPL Token rule: Token accounts can only be closed when balance == 0.
Token-2022: Accounts with TransferFeeConfig may have withheld fees. Must harvest before close.

6. Reinitialization Prevention

For each account type that can be initialized:

init_if_needed WARNING: This attribute allows reinitialization if the account already exists. It is a known footgun.
Safe pattern: Use init (fails if account exists) + manual is_initialized flag for manual programs.
Attack: Re-initialize an account to reset its state (e.g., reset reward counter, change authority).

Finding Template

**ID**: [AL-N]
**Severity**: [revival = High, stranded rent = Medium, reinit = High]
**Step Execution**: ✓1,2,3,4,5,6 | ✗(reasons) | ?(uncertain)
**Rules Applied**: [S4:✓, R9:✓/✗]
**Location**: program/src/{file}.rs:LineN
**Title**: [Lifecycle issue] in [instruction] enables [attack]
**Description**: [Specific lifecycle vulnerability with code trace]
**Impact**: [Fund theft via revival / stranded assets / state reset]

Step Execution Checklist (MANDATORY)