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medium Access Control SWC-106 CWE-284

pause()/unpause() Without Access Control

SAFE-0227 Access Control Checked automatically by the scanner
1

What goes wrong

An emergency pause/unpause is public or has no modifier, letting anyone halt (grief) the protocol or, worse, un-pause it during an incident the team is trying to contain.

2

The vulnerable pattern

proof of concept — how it is exploited
// function pause() public { _pause(); }
// attacker calls pause() repeatedly -> the protocol is frozen at will (DoS).
3

How to fix it

the pattern that is safe
function pause() external onlyRole(PAUSER_ROLE) { _pause(); }
function unpause() external onlyRole(PAUSER_ROLE) { _unpause(); }
◆
Gate pause/unpause behind a dedicated role.
4

Where this has happened

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

$1.43B · 2025 Bybit Access control · 2025 $624M · 2022 Ronin Network Access control · 2022 $611M · 2021 Poly Network Access control · 2021 $291M · 2026 KelpDAO rsETH Access control · 2026
5

Related vulnerabilities in Access Control

SAFE-0006Missing Access Control on Privileged Function critical · Access Control SAFE-0008Unprotected Initializer / Initialization critical · Access Control SAFE-0010Privilege Escalation via Role Misconfiguration critical · Access Control SAFE-0015Backdoor / Hidden Privileged Function critical · Access Control SAFE-0116Unprotected selfdestruct critical · Access Control SAFE-0007tx.origin Used for Authentication high · Access Control SAFE-0009Missing Initializer Disable on Implementation high · Access Control SAFE-0013Authorization Through msg.data / Signature Confusion high · Access Control
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