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low Best Practice No SWC entry CWE-778

Missing Event Emission on Critical Action

SAFE-0075 Best Practice Checked automatically by the scanner
1

What goes wrong

State-changing admin/critical actions emit no events, hampering off-chain monitoring, incident response, and transparency (and sometimes hiding malicious changes).

2

How to fix it

the pattern that is safe
event OwnerChanged(address indexed prev, address indexed next);
function setOwner(address n) external onlyOwner { emit OwnerChanged(owner,n); owner=n; }
◆
Emit events for all critical state changes.
3

Where this has happened

Largest recorded losses in the same failure class — related, not the same bug:

$69.3M · 2023 Curve Finance · Vyper compiler Compiler / toolchain + Reentrancy · 2023
4

Related vulnerabilities in Best Practice

SAFE-0076Use of Deprecated / Dangerous Constructs (selfdestruct, suicide, throw) medium · Best Practice SAFE-0079Outdated Compiler / Known Compiler Bug Exposure medium · Best Practice SAFE-0083Emergency Pause Missing / Pause Bypass medium · Best Practice SAFE-0077Dead Code / Unreachable or Unused Critical Variable low · Best Practice SAFE-0078Floating / Unlocked Pragma low · Best Practice SAFE-0097Assert/Require Misuse and Improper Error Handling low · Best Practice SAFE-0138Floating / Unlocked Pragma low · Best Practice SAFE-0139Deprecated / Unsafe Language Constructs low · Best Practice
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