rules:
- id: missing-self-transfer-check-ercx
  languages:
  - solidity
  message: >-
    Missing check for 'from' and 'to' being the same before updating balances
    could lead to incorrect balance manipulation on self-transfers.
    Include a check to ensure 'from' and 'to' are not the same before updating balances to prevent balance manipulation during self-transfers.
  severity: ERROR
  metadata:
    category: security
    technology:
    - blockchain
    - solidity
    cwe: 'CWE-682: Incorrect Calculation'
    subcategory:
    - vuln
    confidence: HIGH
    likelihood: HIGH
    impact: HIGH
    owasp:
    - A7:2021 Identification and Authentication Failures
    references:
    - https://blog.verichains.io/p/miner-project-attacked-by-vulnerabilities
    - https://x.com/shoucccc/status/1757777764646859121
  patterns:
  - pattern-either:
    - pattern: |
        _balances[$FROM] = $FROM_BALANCE - value;
    - pattern: |
        _balances[$TO] = $TO_BALANCE + value;
  - pattern-not-inside: |
      if ($FROM != $TO) {
        ...
        _balances[$FROM] = $FROM_BALANCE - value;
        ...
        _balances[$TO] = $TO_BALANCE + value;
        ...
      }
  - pattern-inside: |
      function _update(address $FROM, address $TO, uint256 value, bool mint) internal virtual {
        ...
      }