Platypus attack exploited incorrect ordering of code, auditor claims
The $8m Platypus flash mortgage assault was made attainable due to code that was in the unsuitable order, in accordance with a submit mortem report from Platypus auditor Omniscia. The auditing firm claims the problematic code didn’t exist within the model they noticed.
In mild of the latest @Platypusdefi incident the https://t.co/30PzcoIJnt crew has ready a technical autopsy evaluation describing how the exploit unravelled in nice particulars.
Make sure to comply with @Omniscia_sec to obtain extra safety updates!https://t.co/cf784QtKPK pic.twitter.com/egHyoYaBhn
— Omniscia (@Omniscia_sec) February 17, 2023
In response to the report, the Platypus MasterPlatypusV4 contract “contained a deadly false impression in its emergencyWithdraw mechanism” which made it carry out “its solvency verify earlier than updating the LP tokens related to the stake place.”
The report emphasised that the code for the emergencyWithdraw operate had the entire mandatory components to stop an assault, however these components had been merely written within the unsuitable order, as Omniscia defined:
“The difficulty may have been prevented by re-ordering the MasterPlatypusV4::emergencyWithdraw statements and performing the solvency verify after the consumer’s quantity entry has been set to 0 which might have prohibited the assault from going down.”
Omnisia admitted that they audited a model of the MasterPlatypusV4 contract from Nov. 21 to Dec. 5, 2021. Nevertheless, this model “contained no integration factors with an exterior platypusTreasure system” and subsequently didn’t comprise the misordered traces of code. From Omniscia’s perspective, this suggests that the builders should have deployed a brand new model of the contract in some unspecified time in the future after the audit was made.
Associated: Raydium declares particulars of hack, proposes compensation for victims
The auditor claims that the contract implementation at Avalanche (AVAX) C-Chain tackle 0xc007f27b757a782c833c568f5851ae1dfe0e6ec7 is the one which was exploited. Traces 582-584 of this contract seem to name a operate referred to as “isSolvent” on the PlatypusTreasure contract, and contours 599-601 seem to set the consumer’s quantity, issue, and rewardDebt to zero. Nevertheless, these quantities are set to zero after the “isSolvent” operate has already been referred to as.
The Platypus crew confirmed on Feb. 16 that the attacker exploited a “flaw in [the] USP solvency verify mechanism,” however the crew didn’t initially present additional element. This new report from the auditor sheds additional mild on how the attacker could have been in a position to accomplish the exploit.
The Platypus crew introduced on Feb. 16 that the assault had occurred. It has tried to contact the hacker and get the funds returned in trade for a bug bounty. The attacker used flashed loans to carry out the exploit, which has similarities to the technique used within the Defrost Finance exploit of Dec. 25.