Tornado Cash Governance Overtaken - Revision history

Azoundria: Another 30 minutes complete.

2023-06-27T03:52:49Z

Another 30 minutes complete.

Azoundria: Another 30 minutes complete.

2023-06-14T22:16:06Z

Another 30 minutes complete.

← Older revision		Revision as of 16:16, 14 June 2023
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	{{~~Imported~~ Case Study~~\|source=https://www.quadrigainitiative.com/casestudy/tornadocashgovernanceovertaken.php~~}}[[File:Tornadocash.jpg\|thumb\|Tornado Cash]]TornadoCash fell victim to a malicious governance proposal, putting control of various aspects of the smart contract in the hands of a single address. This was accomplished through a clever "bait and switch" with a smart contract that delegated calls to another. The original smart contract was self destructed and a new smart contract was deployed to the same address. The financial damage seems minimal, and there is reports that the attacker may be reverting the damage and relinquishing control.		{{Case Study Under Construction}}[[File:Tornadocash.jpg\|thumb\|Tornado Cash]]TornadoCash fell victim to a malicious governance proposal, putting control of various aspects of the smart contract in the hands of a single address. This was accomplished through a clever "bait and switch" with a smart contract that delegated calls to another. The original smart contract was self destructed and a new smart contract was deployed to the same address. The financial damage seems minimal, and there is reports that the attacker may be reverting the damage and relinquishing control.

	== About Tornado Cash ==		== About Tornado Cash ==
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	== What Happened ==		== What Happened ==
	The TornadoCash governance mechanism was overtaken by a trojan horse proposal. After the community voted to pass the proposal, the contract was self destructed and replaced with a version which granted the attacker complete control over the TornadoCash governance (although no ability to withdraw funds). The attacker eventually published a proposal to revert their control back to the community.		The TornadoCash governance mechanism was overtaken by a trojan horse proposal. After the community voted to pass the proposal, the contract was self destructed and replaced with a version which granted the attacker complete control over the TornadoCash governance (although governance granted them no ability to withdraw funds). The attacker eventually published a proposal to revert their control back to the community.
	{\| class="wikitable"		{\| class="wikitable"
	\|+Key Event Timeline - Tornado Cash Governance Overtaken		\|+Key Event Timeline - Tornado Cash Governance Overtaken
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	== Technical Details ==		== Technical Details ==
	~~This section includes specific detailed technical analysis~~ of any ~~security breaches~~ which ~~happened~~. ~~What specific software vulnerabilities contributed~~ to the ~~problem~~ and ~~how were~~ they ~~exploited?~~		The exploit consisted of three stages:

			# Preparing the smart contract.
			# Getting the smart contract approved through governance.
			# Switching to enable the smart contract.

			=== Smart Contract Preparation ===
			The address of a smart contract is generated based on a combination of two things:

			* A nonce, which is incremented each time a transaction happens in the given address, such as deploying a smart contract.
			* The smart contract bytecode, which represents the instructions to execute and does not include the values of any variables.

			The above two inputs are hashed (passed through a one-way encryption function). As a key property of the hash, the output is predictable. So, if the first transaction on an address has a given set of bytecode, it will always get the same smart contract address.

			Smart contracts can delegate functionality to other smart contracts. They can do this dynamically by invoking the call on a smart contract in a stored address. These types of calls are commonly used in decentralized finance, as they allow for future upgradeability.

			As such, if the same smart contract is deployed twice by a wallet with the same nonce, it receives the same address. Even though the smart contract has the same byte code, through the powers of delegation to other smart contracts, the actual functionality can be adjusted.

			=== Getting Approval For Smart Contract ===
			TornadoCash was open source and used a decentralized governance mechanism. While anyone can propose a modification, community support is required. The TORN token is widely held, and there isn't a large honey-pot which is accessible from governance, so that budget of an attacker is likely to be limited. Attempting to buy a majority of tokens also requires those tokens to be available and sold in the market, and this is likely to arouse suspicion.

			Instead, the attacker used clever social engineering. They gained approval for their smart contract by claiming to have used the exact same logic as in an earlier proposal. To improve their success against an open source community, they copied most aspects of the code from that contract with only minor additions. They named the new function "emergencyStop" so it would look like it had a legitimate purpose of being used in emergencies.

			This was a novel attack which most developers hadn't seen before, so in this particular case no one from the community was able to come forward and warn about the risks.

			=== The Final Bait And Switch ===



	Exploiter Addresses: <ref name="etherscan-11113" /> <ref name="etherscan-11114" />		Exploiter Addresses: <ref name="etherscan-11113" /> <ref name="etherscan-11114" />
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	== Total Amount Lost ==		== Total Amount Lost ==
	~~The total amount at risk has been estimated at $275,000,000 USD.~~ The total amount lost has been estimated at $59,000 USD.		The total amount lost has been estimated at $59,000 USD. <ref name="coinmarketcap-11128" /> TBD NOVA pool at risk?

	<ref name="coinmarketcap-11128" />

	How much was lost and how was it calculated? If there are conflicting reports, which are accurate and where does the discrepancy lie?		How much was lost and how was it calculated? If there are conflicting reports, which are accurate and where does the discrepancy lie?
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	== Ongoing Developments ==		== Ongoing Developments ==
	~~What parts~~ of ~~this case are still remaining to be concluded?~~		While the possibility of a future governance exploit is definitely possible, it seems probable that the community will exercise increased care on future proposals.
	== Individual Prevention Policies ==		== Individual Prevention Policies ==
	{{Prevention:Individual:Avoid Using Smart Contracts}}		{{Prevention:Individual:Avoid Using Smart Contracts}}

Azoundria: Another 30 minutes complete. Prevention added.

2023-05-30T18:34:47Z

Another 30 minutes complete. Prevention added.

← Older revision		Revision as of 12:34, 30 May 2023
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	\|May 20th, 2023 4:00:00 PM MDT		\|May 20th, 2023 4:00:00 PM MDT
	\|Correction With Nova At Risk		\|Correction With Nova At Risk
	\|<ref>[https://twitter.com/samczsun/status/1660042906500214784 samczsun - "Correction: @CellierLael correctly pointed out that Tornado Cash Nova, deployed to Gnosis Chain, is a proxy that is administered by governance. Therefore, the attacker is also able to drain all of the ETH in that pool by upgrading the contract" - Twitter] (May 29, 2023)</ref>.		\|"@CellierLael correctly pointed out that Tornado Cash Nova, deployed to Gnosis Chain, is a proxy that is administered by governance. Therefore, the attacker is also able to drain all of the ETH in that pool by upgrading the contract"<ref>[https://twitter.com/samczsun/status/1660042906500214784 samczsun - "Correction: @CellierLael correctly pointed out that Tornado Cash Nova, deployed to Gnosis Chain, is a proxy that is administered by governance. Therefore, the attacker is also able to drain all of the ETH in that pool by upgrading the contract" - Twitter] (May 29, 2023)</ref><ref>[https://gnosisscan.io/address/0xd692fd2d0b2fbd2e52cfa5b5b9424bc981c30696 TornadoCash Nova - Gnosis Scan] (May 30, 2023)</ref>.
	\|-		\|-
	\|May 21st, 2023 3:23:00 AM MDT		\|May 21st, 2023 3:23:00 AM MDT
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	\|Apporv Lathey Technical Deep Dive		\|Apporv Lathey Technical Deep Dive
	\|NTFX protocol developer Apoorv Lathey published a deep technical dive into what happened on Twitter<ref name="apoorvlatheytwitter-11126" />.		\|NTFX protocol developer Apoorv Lathey published a deep technical dive into what happened on Twitter<ref name="apoorvlatheytwitter-11126" />.
			\|-
			\|May 22nd, 2023 7:18:00 AM MDT
			\|Revert Transaction Proposed
			\|This news is shared on Twitter<ref>[https://twitter.com/CryptoLycus/status/1660636155141046272 CryptoLycus - "An attacker has submitted a proposal to undo the recent attack on #TornadoCash's governance" - Twitter] (May 30, 2023)</ref><ref>[https://twitter.com/lmc_security/status/1661282727960752133 Lucas Martin Calderon - "On May 21st, the attacker submitted another proposal to revert the hack and return the tokens. That is, the ones that he has not sold… The smart contract seems simple enough to be malicious, we will see how it plays out." - Twitter] (May 30, 2023)</ref><ref>[https://twitter.com/thecryptosquad_/status/1660820391374487552 The CryptoSquad - "@TornadoCash’s $TORN surge as attacker submitted proposal to undo attack." - Twitter] (May 30, 2023)</ref><ref>[https://twitter.com/ducthangdcn/status/1663017340303450112 ducthangdcn - "Good new " - Twitter] (May 30, 2023)</ref>.
	\|-		\|-
	\|May 23rd, 2023 8:39:00 AM MDT		\|May 23rd, 2023 8:39:00 AM MDT
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	Meanwhile, our @MistTrack_io team analyzed the addresses of the proposal voters and made some interesting discoveries</blockquote>		Meanwhile, our @MistTrack_io team analyzed the addresses of the proposal voters and made some interesting discoveries</blockquote>

			=== Lucas Martin Calderon Technical Overview ===
			A brief technical overview was published by Lucas Martin Calderon<ref>[https://twitter.com/lmc_security/status/1660354078503759874 Lucas Martin Calderon - @TornadoCash has been hacked in a way I’ve never seen before When was the last time you saw the attack below, using SELFDESTRUCT and metamorphic contracts?" - Twitter] (May 30, 2023)</ref>.<blockquote>@TornadoCash has been hacked in a way I’ve never seen before When was the last time you saw the attack below, using SELFDESTRUCT and metamorphic contracts?

			High-level attack exploit: attacker gains 1.2M votes from the Tornado Cash governance vault worth millions of USD by using a malicious governance proposal contract.

			The attacker was able to change the bytecode of the smart contract using metamorphic contracts and SELFDESTRUCT

			It seems that they pulled it off using a fork of CREATE3 and CREATE2 library from solmate.

	~~<nowiki>https://twitter~~.~~com/samczsun/status/1660042906500214784~~</~~nowiki~~>		On May 21st, the attacker submitted another proposal to revert the hack and return the tokens. That is, the ones that he has not sold… The smart contract seems simple enough to be malicious, we will see how it plays out.</blockquote>

	=== Apoorv Lathey Technical Deep Dive ===		=== Apoorv Lathey Technical Deep Dive ===
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	What parts of this case are still remaining to be concluded?		What parts of this case are still remaining to be concluded?
	== Individual Prevention Policies ==		== Individual Prevention Policies ==
	{{Prevention:~~Individuals~~:~~Placeholder~~}}		{{Prevention:Individual:Avoid Using Smart Contracts}}

	{{Prevention:Individuals:End}}		{{Prevention:Individuals:End}}

	== Platform Prevention Policies ==		== Platform Prevention Policies ==
	{{Prevention:Platforms:~~Placeholder~~}}		{{Prevention:Platforms:Regular Audit Procedures}}

			It could be enforced at the community or platform level to ensure that all TornadoCash protocol upgrades have at least two separate third-party expert opinions.

	{{Prevention:Platforms:End}}		{{Prevention:Platforms:End}}

	== Regulatory Prevention Policies ==		== Regulatory Prevention Policies ==
	{{Prevention:Regulators:~~Placeholder~~}}		{{Prevention:Regulators:Platform Security Assessments}}

			It could be community-enforced to ensure that all TornadoCash protocol upgrades have at least two separate third-party expert opinions.

	{{Prevention:Regulators:End}}		{{Prevention:Regulators:End}}

Azoundria at 16:33, 30 May 2023

2023-05-30T16:33:46Z

← Older revision		Revision as of 10:33, 30 May 2023
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	<ref name="blocksecteamtwitter-11122">[https://twitter.com/BlockSecTeam/status/1660214665429876740 BlockSecTeam - "The key to the success of the Tornado Cash DAO attack is that 1) blindly vote -- vote without knowing the consequence; 2) a proposal contract can be updated through a well-designed trick -- create and create2." - Twitter] (May 24, 2023)</ref>		<ref name="blocksecteamtwitter-11122">[https://twitter.com/BlockSecTeam/status/1660214665429876740 BlockSecTeam - "The key to the success of the Tornado Cash DAO attack is that 1) blindly vote -- vote without knowing the consequence; 2) a proposal contract can be updated through a well-designed trick -- create and create2." - Twitter] (May 24, 2023)</ref>
	<ref name="googledoc-11123">[https://docs.google.com/presentation/d/1QgYUmowhFxjuh18eV7zIlz0icr4MfnjKOJJ__yYVz-w/edit TornadoCash DAO Attack - BlockSec Google Slides] (May 24, 2023)</ref>		<ref name="googledoc-11123">[https://docs.google.com/presentation/d/1QgYUmowhFxjuh18eV7zIlz0icr4MfnjKOJJ__yYVz-w/edit TornadoCash DAO Attack - BlockSec Google Slides] (May 24, 2023)</ref>
	~~<ref name="ameensoltwitter-11124">[https://twitter.com/ameensol/status/1660267467795570689 @ameensol Twitter] (May 24, 2023)</ref>~~
	<ref name="ameensoltwitter-11125">[https://twitter.com/ameensol/status/1660265160701870081 Ameen Soleimani - "there is about $1m in the nova contract, that the governance attacker can rugpull via proposal. fortunately the proposal would take 7 days to execute. best not wait!" - Twitter] (May 24, 2023)</ref>		<ref name="ameensoltwitter-11125">[https://twitter.com/ameensol/status/1660265160701870081 Ameen Soleimani - "there is about $1m in the nova contract, that the governance attacker can rugpull via proposal. fortunately the proposal would take 7 days to execute. best not wait!" - Twitter] (May 24, 2023)</ref>
	<ref name="apoorvlatheytwitter-11126">[https://twitter.com/apoorvlathey/status/1660355712353189888 Apoorv Lathey - "Technical Deep Dive: How Tornado Cash governance exploiter was able to deploy a new malicious contract at the same address" - Twitter] (May 24, 2023)</ref>		<ref name="apoorvlatheytwitter-11126">[https://twitter.com/apoorvlathey/status/1660355712353189888 Apoorv Lathey - "Technical Deep Dive: How Tornado Cash governance exploiter was able to deploy a new malicious contract at the same address" - Twitter] (May 24, 2023)</ref>

Azoundria: Another 30 minutes complete. All sources merged in.

2023-05-29T16:38:28Z

Another 30 minutes complete. All sources merged in.

Show changes

Azoundria: 30 minutes completed.

2023-05-25T19:38:14Z

30 minutes completed.

Show changes

Azoundria: Created page with "{{Imported Case Study|source=https://www.quadrigainitiative.com/casestudy/tornadocashgovernanceovertaken.php}} {{Unattributed Sources}} Tornado CashTornadoCash fell victim to a malicious governance proposal, putting control of various aspects of the smart contract in the hands of a single address. This was accomplished through a clever "bait and switch" with a smart contract that delegated calls to another. The original smart contract was..."

2023-05-25T17:08:00Z

Created page with "{{Imported Case Study|source=https://www.quadrigainitiative.com/casestudy/tornadocashgovernanceovertaken.php}} {{Unattributed Sources}} thumb|Tornado CashTornadoCash fell victim to a malicious governance proposal, putting control of various aspects of the smart contract in the hands of a single address. This was accomplished through a clever "bait and switch" with a smart contract that delegated calls to another. The original smart contract was..."

New page

{{Imported Case Study|source=https://www.quadrigainitiative.com/casestudy/tornadocashgovernanceovertaken.php}}
{{Unattributed Sources}}

[[File:Tornadocash.jpg|thumb|Tornado Cash]]TornadoCash fell victim to a malicious governance proposal, putting control of various aspects of the smart contract in the hands of a single address. This was accomplished through a clever "bait and switch" with a smart contract that delegated calls to another. The original smart contract was self destructed and a new smart contract was deployed to the same address. The financial damage seems minimal, and there is reports that the attacker may be reverting the damage and relinquishing control.

This is a global/international case not involving a specific country.<ref name="rektnews-11109" /><ref name="deomaiustwitter-11110" /><ref name="forums-11111" /><ref name="defillama-11112" /><ref name="etherscan-11113" /><ref name="etherscan-11114" /><ref name="samczsuntwitter-11115" /><ref name="openchain-11116" /><ref name="etherscan-11117" /><ref name="openchain-11118" /><ref name="openchain-11119" /><ref name="openchain-11120" /><ref name="slowmistteamtwitter-11121" /><ref name="blocksecteamtwitter-11122" /><ref name="googledoc-11123" /><ref name="ameensoltwitter-11124" /><ref name="ameensoltwitter-11125" /><ref name="apoorvlatheytwitter-11126" /><ref name="tornadocasharchive-11127" /><ref name="coinmarketcap-11128" /><ref name="tornadocashdocsarchive-11129" />

== About Tornado Cash ==
TornadoCash is "[a] fully decentralized protocol for private transactions on Ethereum." and "in the crypto-space."

As a decentralized protocol, Tornado.Cash smart contracts have been implemented within the Ethereum blockchain, making them immutable. They can neither be changed nor tampered with. Therefore, nobody - including the original developers - can modify or shut them down. All governance and mining smart contracts are deployed by the community in a decentralized manner.

As a non-custodial protocol, users keep custody of their cryptocurrencies while operating Tornado.Cash. This means that at each deposit, they are provided with the private key enabling the access to the deposited funds, which gives users complete control over their assets."

"Tornado Cash improves transaction privacy by breaking the on-chain link between source and destination addresses. It uses a smart contract that accepts ETH & other tokens deposits from one address and enables their withdrawal from a different address."

"Since its inception in 2019, Tornado Cash has been operating on the Ethereum blockchain. The protocol has been offering diversified fixed amount pools for six tokens (ETH, DAI, cDAI, USDC, USDT & WBTC) handled by the Ethereum blockchain.

Since June 2021, in addition to the Ethereum blockchain, Tornado Cash smart contracts have also been deployed on other side-chains & blockchains. These deployments enabled the tool to either support new tokens or benefit from Layer-2 advantages, such as faster and cheaper transactions."

"In a whirlwind of events, Tornado Cash's governance has been taken hostage via a trojan horse proposal, effectively granting control of the DAO to a single address."

"On 2023/05/20 at 07:25:11 UTC, Tornado Cash governance effectively ceased to exist. Through a malicious proposal, an attacker granted themselves 1,200,000 votes. As this is more than the ~700,000 legitimate votes, they now have full control."

"when the attacker created their malicious proposal, they claimed to have used the same logic as an earlier proposal which had passed. However, that wasn't exactly the truth, because they added an extra function"

"Once the proposal was passed by voters, the attacker simply used the emergencyStop function to update the proposal logic to grant themselves the fake votes"

"a proposal contract can be updated through a well-designed trick -- create and create2."

"2/ The attack is a sophisticatedly designed one. 1) The attacker used the name emergencyStop to hide the intent; 2) the attacker used a trick of combining CREATE/CREATE2 to create a contract with the same address with different bytecode."

"Proposal Contract was deployed via CREATE.
The address for such contracts is derived by hashing deployer address and deployer nonce.

Note: Smart contracts start with nonce = 1

So, Proposal addr: 0xc50 = hash(0x7dc, 1)"

"After governance approved this Proposal Contract, the attacker called its emergencyStop function (which they added maliciously).

This resulted in the contract calling selfdestruct

Then the Deployer contract was self-destructed as well! (re-setting its nonce to 0)"

"The attacker used CREATE2 to deploy the exact same deployer bytecode.

Because of the same bytecode, the contract was deployed at the same address as before: 0x7dc

The nonce then became 1 (as address now had smart contract code)"

"The attacker then called "create(bytes)" function on the Deployer contract, but this time passing a completely new bytecode for their Malicious contract

As the nonce & deployer address were same as before, this resulted in the Malicious contract at the same address as Proposal"

"While the contracts do not allow for draining of the ~$275M in the privacy pools themselves, the exploiter gained control of the TORN governance token, the power to modify the router to reroute deposits/withdrawals, and admin status over Nova, the Gnosis chain deployment."

"Through governance control, the attacker can:
- withdraw all of the locked votes
- drain all of the tokens in the governance contract
- brick the router

However, the attacker still can't:
- drain individual pools"

"In this case, they simply withdrew 10,000 votes as TORN and sold it all"

"However, it seems not all is lost.

Yesterday, just before midday UTC, the exploiter published another proposal to revert the changes.

As long as there are no nasty surprises this time, this could be a bullet dodged for the Tornado Cash community."

This is a global/international case not involving a specific country.

The background of the exchange platform, service, or individuals involved, as it would have been seen or understood at the time of the events.

Include:

* Known history of when and how the service was started.
* What problems does the company or service claim to solve?
* What marketing materials were used by the firm or business?
* Audits performed, and excerpts that may have been included.
* Business registration documents shown (fake or legitimate).
* How were people recruited to participate?
* Public warnings and announcements prior to the event.

Don't Include:
* Any wording which directly states or implies that the business is/was illegitimate, or that a vulnerability existed.
* Anything that wasn't reasonably knowable at the time of the event.
There could be more than one section here. If the same platform is involved with multiple incidents, then it can be linked to a main article page.

== The Reality ==
This sections is included if a case involved deception or information that was unknown at the time. Examples include:

* When the service was actually started (if different than the "official story").
* Who actually ran a service and their own personal history.
* How the service was structured behind the scenes. (For example, there was no "trading bot".)
* Details of what audits reported and how vulnerabilities were missed during auditing.

== What Happened ==
The specific events of the loss and how it came about. What actually happened to cause the loss and some of the events leading up to it.
{| class="wikitable"
|+Key Event Timeline - Tornado Cash Governance Overtaken
!Date
!Event
!Description
|-
|May 20th, 2023 1:25:11 AM MDT
|Governance Exploit
|Blockchain transaction.
|}

== Technical Details ==
This section includes specific detailed technical analysis of any security breaches which happened. What specific software vulnerabilities contributed to the problem and how were they exploited?

== Total Amount Lost ==
The total amount at risk has been estimated at $275,000,000 USD. The total amount lost has been estimated at $59,000 USD.

How much was lost and how was it calculated? If there are conflicting reports, which are accurate and where does the discrepancy lie?

== Immediate Reactions ==
How did the various parties involved (firm, platform, management, and/or affected individual(s)) deal with the events? Were services shut down? Were announcements made? Were groups formed?

== Ultimate Outcome ==
What was the end result? Was any investigation done? Were any individuals prosecuted? Was there a lawsuit? Was any tracing done?

== Total Amount Recovered ==
The total amount recovered is unknown.

What funds were recovered? What funds were reimbursed for those affected users?

== Ongoing Developments ==
What parts of this case are still remaining to be concluded?
== Individual Prevention Policies ==
{{Prevention:Individuals:Placeholder}}

{{Prevention:Individuals:End}}

== Platform Prevention Policies ==
{{Prevention:Platforms:Placeholder}}

{{Prevention:Platforms:End}}

== Regulatory Prevention Policies ==
{{Prevention:Regulators:Placeholder}}

{{Prevention:Regulators:End}}

== References ==
<references><ref name="rektnews-11109">[https://rekt.news/tornado-gov-rekt/ Rekt - Tornado Cash Governance - REKT] (May 24, 2023)</ref>

<ref name="deomaiustwitter-11110">[https://twitter.com/deomaius/status/1649910385305108489 @deomaius Twitter] (May 24, 2023)</ref>

<ref name="forums-11111">[https://forums.tornadocash.community/t/18-audit-reimbursement-and-remuneration-q2/150 #18: Audit reimbursement and remuneration Q2 - Proposal - tornadocash.community] (May 24, 2023)</ref>

<ref name="defillama-11112">[https://defillama.com/protocol/tornado-cash https://defillama.com/protocol/tornado-cash] (May 24, 2023)</ref>

<ref name="etherscan-11113">[https://etherscan.io/address/0x092123663804f8801b9b086b03b98d706f77bd59 Tornado.Cash Governance Exploiter | Address 0x092123663804f8801b9b086b03b98d706f77bd59 | Etherscan] (May 24, 2023)</ref>

<ref name="etherscan-11114">[https://etherscan.io/address/0x592340957ebc9e4afb0e9af221d06fdddf789de9 Tornado.Cash Governance Exploiter 2 | Address 0x592340957ebc9e4afb0e9af221d06fdddf789de9 | Etherscan] (May 24, 2023)</ref>

<ref name="samczsuntwitter-11115">[https://twitter.com/samczsun/status/1660012956632104960 @samczsun Twitter] (May 24, 2023)</ref>

<ref name="openchain-11116">[https://openchain.xyz/trace/ethereum/0x3274b6090685b842aca80b304a4dcee0f61ef8b6afee10b7c7533c32fb75486d Transaction Tracer] (May 24, 2023)</ref>

<ref name="etherscan-11117">[https://etherscan.io/address/0xC503893b3e3c0C6b909222b45f2a3a259a52752D Proposal | Address 0xC503893b3e3c0C6b909222b45f2a3a259a52752D | Etherscan] (May 24, 2023)</ref>

<ref name="openchain-11118">[https://openchain.xyz/trace/ethereum/0xd3a570af795405e141988c48527a595434665089117473bc0389e83091391adb Transaction Tracer] (May 24, 2023)</ref>

<ref name="openchain-11119">[https://openchain.xyz/trace/ethereum/0xa7d20ccdbc2365578a106093e82cc9f6ec5d03043bb6a00114c0ad5d03620122 Transaction Tracer] (May 24, 2023)</ref>

<ref name="openchain-11120">[https://openchain.xyz/trace/ethereum/0x65fa5b475f34a954a10f88f2c84f316a048a0e67d273c7abb098717b1a4a46a3 Transaction Tracer] (May 24, 2023)</ref>

<ref name="slowmistteamtwitter-11121">[https://twitter.com/SlowMist_Team/status/1660252800406659073 @SlowMist_Team Twitter] (May 24, 2023)</ref>

<ref name="blocksecteamtwitter-11122">[https://twitter.com/BlockSecTeam/status/1660214665429876740 @BlockSecTeam Twitter] (May 24, 2023)</ref>

<ref name="googledoc-11123">[https://docs.google.com/presentation/d/1QgYUmowhFxjuh18eV7zIlz0icr4MfnjKOJJ__yYVz-w/edit TC_Dao_Attack_BlockSec - Google Slides] (May 24, 2023)</ref>

<ref name="ameensoltwitter-11124">[https://twitter.com/ameensol/status/1660267467795570689 @ameensol Twitter] (May 24, 2023)</ref>

<ref name="ameensoltwitter-11125">[https://twitter.com/ameensol/status/1660265160701870081 @ameensol Twitter] (May 24, 2023)</ref>

<ref name="apoorvlatheytwitter-11126">[https://twitter.com/apoorvlathey/status/1660355712353189888 @apoorvlathey Twitter] (May 24, 2023)</ref>

<ref name="tornadocasharchive-11127">[https://web.archive.org/web/20220606050106/https://tornado.cash/ Tornado.cash] (May 24, 2023)</ref>

<ref name="coinmarketcap-11128">[https://coinmarketcap.com/currencies/torn/historical-data/ https://coinmarketcap.com/currencies/torn/historical-data/] (May 24, 2023)</ref>

<ref name="tornadocashdocsarchive-11129">[https://web.archive.org/web/20220619103115/https://docs.tornado.cash/general/readme Introduction to Tornado Cash - tornado.cash] (May 24, 2023)</ref></references>