Examples of privacy leaks used to trace monero
These hurdles make it hard to use monero privately
The Justice Department says they found the admin of Incognito Market by tracing his monero. source - January 2024
Key quote: "cryptocurrency was first swapped through Swapping Service-1 and converted...to Monero... After the swap, the funds were transferred into [the perp’s] Crypto Account...[at the KYC exchange]..." source - page 25
Attack type: Eve-Alice-Eve attack with timing analysis
Data leaked by the target:
Data used by the attacker: The attacker's report used the amounts received by the target, the time of the target's "send" transactions, and the amounts sent in each of those transactions. It did not use the info about the target's stealth public keys, their ring signatures, or their fee data. The report argued that the time and amounts in the analyzed transactions demonstrated that the target did the following procedure several times: the target swapped criminal proceeds into monero via a no-KYC exchange, withdrew them to a monero wallet, and then, within minutes, sent similar amounts -- sometimes identical amounts -- to a KYC exchange, where they sold the monero for fiat currency. The KYC exchange had the target's KYC info, which is how the authorities nabbed him.
Chainalysis says they found a Columbian drug seller by tracing his monero. source - September 2024
Key quote: "And so that was a really exciting moment for us because we were able to start using just this list of Morphtoken swaps occurring on the monero blockchain---very little information, and not many breadcrumbs to follow. We were able to trace that forward on the monero blockchain to an rpc ip observation and then leverage other chainalysis tools in order to find more potential results that we can return to law enforcement." source - 38:37
Attack type: Eve-Alice-Eve attack with poisoned outputs and RPC connections
Data leaked by the target:
Data used by the attacker: The attacker's report used all of the above-listed leaks except for the fee data. (Although they did not use the fee data, they mentioned that it is sometimes useful for fingerprinting wallets, e.g. they mentioned that widely-used services like exchanges, darknet markets, and custodial wallets tend to set larger fees than do users of self-custodial wallets.) The target's use of a RPC connections was particularly meaningful because the target eventually revealed their ip address when their wallet connected to one of the attacker's nodes to broadcast a transaction, and the attacker was then able to use that ip address to find the target's real identity. To ensure that this transaction was created by the target, however, they had to do the following analysis: in several transactions, the attacker successfully used off-chain data about the "decoy" public keys in the ring signatures to eliminate some decoys, and at least once they identified the target as the true spend. They used these transaction analysis techniques several times, looking for transactions where the target connected to one of the attacker's nodes to broadcast a transaction via an RPC connection. The attacker found several transactions that did this, most of which could not be used to identify the recipient because he used a VPN to guard his ip address. But in one of them, he did not use a vpn, so they found his ip address and nabbed him. The only thing the attackers used timing analysis for, in this case, was to identify which transactions were sent before and after the Dandelion upgrade in monero, which makes it harder to identify the ip addresses of monero senders who use their own nodes.
Finnish authorities say they traced a ransomware operator’s monero from a swap service to a monero wallet to binance. The description of the case makes it sound like they used poisoned outputs, but there is evidence that the perpetrator leaked his monero private keys shortly before his arrest, which would have enabled a simpler attack: simply look up his transaction history on the blockchain. source - January 2024
Key quote: "[He began] swapping for Monero and then transferring the funds to a dedicated Monero wallet. [Then] the funds were later sent to Binance." source - more details here
Attack type: either an Eve-Alice-Eve attack with poisoned outputs or a tx history lookup
Data leaked by the target:
Data used by the attacker: It depends on which attack the attacker used, which is not clear from the report. Since the target leaked their private keys, the easiest attack would be to look up their transaction history. However, their description of the attack sounds like a case of poisoned outputs. If that is what it was, then the attacker likely used the same data in the Incognito Market report but without the timing info, which they probably substituted with stealth address data as in the Chainalysis report.
Japanese authorities say they analyzed monero wallets found on the computers of 18 criminals who they arrested on other grounds. They then used the data they found in those wallets to charge them with money laundering. source - October 2024
Key quote: "Japanese authorities said they analyzed about 900 of the group’s Monero-based money-laundering transactions...[and] told local media outlet Nikkei that this marked the first time the country’s law enforcement agencies had used Monero transactions to identify criminals." source - more details here
Attack type: tx history lookup
Data leaked by the target:
Data used by the attacker: the attacker simply used the target's private keys to look up their transaction history and then used the resulting information to charge them with money laundering.
Interpol shut down monero-only darknet market Archetyp and says they found its operators by "tracing [their] financial flows". It is not *certain* that this means they traced their monero, but it was a monero-only exchange, so monero is the only type of finances I know they had available to trace. source - June 2025
Key quote: "The takedown follows years of intensive investigative work to map the platform’s technical architecture and identify the individuals behind it. By tracing financial flows, analysing digital forensic evidence, and working closely with partners on the ground, authorities were able to deliver a decisive blow to one of the most prolific drug markets on the dark web." source
Attack type: insufficient data -- the reports only say the attacker traced the target's financial flows without specifying how they did so
Data leaked by the target and used by the attacker: insufficient data for the above-mentioned reasons
Chainalysis reports that after the Bitfinex hacker was arrested, the police found monero wallets on his computer with their private keys, and they then used the private keys to simply look up his XMR transaction history on the blockchain. source - July 2023
Key quote: "agents [got] a search warrant for Lichtenstein and Morgan’s home and cloud storage accounts, where they found files containing details of the cryptocurrency addresses used to move the stolen funds---including their private keys---along with the false information used to open accounts at cryptocurrency exchanges and plans to acquire fake passports. That discovery enabled investigators to trace the flow of funds in its entirety." source
Attack type: tx history lookup
Data leaked by the target:
Data used by the attacker: the attacker simply used the target's private keys to look up his transaction history and then used the resulting information to charge him with theft.
Mastercard offers a monero tracing tool created by Ciphertrace. It is part of their Crypto Source product. source 1, source 2 - August 2021
Key quote: "Ciphertrace takes Monero tracing capabilities to the next level with the ability to follow the flow of funds backwards from the transaction of interest to its source." source - see also this video interview with a Ciphertrace employee about their monero tracing tool
Attack type: many -- see the above-linked video for further details
Data leaked by the target: depends on the case -- the tool uses many techniques to trace monero and some of them are outlined in the above-linked video
Data used by the attacker: depends on the case -- the tool uses many techniques to trace monero