Project: Harpie
Platform: Sherlock
Source, Code

Number: 32
Problem: Signature malleability not protected against
Severity: Medium

Vulnerability detail:
OpenZeppelin has a vulnerability in versions lower than 4.7.3, which can be exploited by an attacker. The project uses a vulnerable version
All of the conditions from the advisory are satisfied: the signature comes in a single bytes argument, ECDSA.recover() is used, and the signatures themselves are used for replay protection checks
oz_vulnerabilitiy

If a user calls changeRecipientAddress(), notices a mistake, then calls changeRecipientAddress() again, an attacker can use signature malleability to re-submit the first change request, as long as the old request has not expired yet.

Impact:
The wrong, potentially now-malicious, address will be the valid change recipient, which could lead to the loss of funds.

Mitigation:
Change oz to version 4.7.3

Fix
#SHERLOCK #REPORT #SIGNATURE #HARPIE

Feb 14, 2023, 1:37 PM

Am I missing something or how exactly is the new oz version protecting signature replay?

Which actually should be fixed by introducing a nonce imo

Feb 14, 2023, 2:04 PM

I added the pics

It lacks the option with length = 64

My understanding of that is if you have some protection from replay attacks and u're using the mapping, you can bypass it with length = 64 signature (signature malleability)

Feb 14, 2023, 2:11 PM

That... still won't prevent it from being reused. Sure it'll prevent usage of different formats, but the exact same signature can be used in replay

Feb 14, 2023, 2:19 PM

We ended the discussion in pm😅🫡

Feb 14, 2023, 2:53 PM