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        • Anyone Can Pass Any Proposal
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    • 16 09 22
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  • Summary:
  • Mitigation:
  • TAGS: #sig
  1. Smart Contracts Security
  2. Code 4 Rena
  3. High Risk Findings

Signature Verification Can Be Bypass With Zero Address

Submitted by (4) vlad_bochok, also found by indijanc, Lambda, and wastewa

PreviousReusing SignaturesNextUntyped Data Signing

Last updated 1 year ago

Summary:

Anyone can add himself as a member of community for any future community. This can be done due to a combination of facts:

  • Non initialized address storage values are defaulted to address(0)

  • addMember doesn't check if community is already created

  • checkSignatureValidity doesn't check for address(0)

Mitigation:

  1. checkSignatureValidity/recoverKey should revert the call if an address == 0.

  2. addMember should have a require(_communityId <= communityCount)

TAGS: #sig

https://code4rena.com/reports/2022-08-rigor/#h-05-add-members-to-the-not-yet-created-community