Non-Custodial XMR Trading 2026: RetoSwap Hack, THORChain, Wagyu

As regulated exchanges pull back from Monero, more XMR trading has moved to peer-to-peer and non-custodial venues. In 2026 those venues had their hardest year: a protocol exploit drained Haveno-based trades, a long-awaited cross-chain DEX integration kept slipping, and a no-KYC swap service leaked order data tied to IP addresses. None of these broke Monero itself, but all of them affect how safely you can get in and out of XMR. Here is a dated rundown.

Summary table

The RetoSwap / Haveno exploit (May 2026)

What Haveno and RetoSwap are

Haveno is open-source, Tor-based peer-to-peer exchange software for trading XMR against fiat and other cryptocurrencies, forked from Bisq. Haveno itself doesn’t run a market. Independent operators run networks on it, and RetoSwap is the largest. Trades are secured with a 2-of-3 multisig wallet: the buyer, the seller and an arbitrator each hold one key, and any two can release funds.

That design is part of the story. According to a security write-up by researcher Sam Bent, Bisq removed the arbitrator from its trade multisig in 2019 (v1.2.0) and moved to 2-of-2 between traders. Haveno brought back the 2-of-3 model with an arbitrator when it forked in 2023.

How the attack worked

Write-ups from Halborn and others describe the same mechanism:

1. The attacker opened a trade as maker or taker, which legitimately gave them one key.
2. During multisig setup they sent a forged ACK message that appeared to come from the arbitrator.
3. The victim’s client accepted it without proper validation and replaced the real arbitrator’s node address with the attacker’s.
4. The attacker now controlled two of three keys. When the victim funded the deposit, the attacker could move the funds alone.

Halborn described the root cause as a flaw in Haveno’s handling of ACK messages during wallet setup, effectively a supply-chain vulnerability for every network built on Haveno, rather than a bug specific to RetoSwap.

Scale and response

• Date: 20 May 2026. Some outlets cite 21 May, which likely reflects time zones.
• Loss: about 7,000 XMR, roughly $2.7 million, as reported by security trackers. Halborn called the figure an estimate.
• Scope: large crypto-to-crypto trades. Fiat trades were reportedly not affected.
• Response: Haveno lead developer woodser told users to pull all offers and stop trading. At 03:43 UTC on 20 May he opened a short patch, PR #2315, titled “refuse to update node address before multisig created.” RetoSwap banned the exploiter’s accounts.
• Traceability: because the funds were in XMR, analysts said tracing or freezing them was effectively impossible.

A second halt in June

On 17 June 2026, ChainCatcher reported that RetoSwap had received a report at 2:02 a.m. Beijing time that the Haveno trade protocol was under attack again. RetoSwap set the minimum client version to 2.0, suspended trading and banned the attacker’s onion address. It said its own systems weren’t breached and the vulnerability sat at the Haveno protocol level. As in May, losses appeared limited to large crypto orders, with fiat traders unaffected. No loss figure was given for the June incident.

Haveno’s security releases since

The Haveno GitHub releases page shows a run of hardening work after the incidents:

• v1.6.0 (24 May): peer identity is always checked against known public key rings.
• v1.8.0 (20 June): verifies the arbitrator’s signature on dispute payouts, verifies deposit responses as coming from the arbitrator, and requires verified senders for all trade setup messages, which closes the class of bug behind the exploit.
• v1.9.0 (6 October): redesigned screens, 24 new payment methods, and “broad security hardening” of trades, disputes and the network layer, including stronger arbitrator-authorization checks and protection against replayed dispute messages.
• v1.10.0 (10 October): usability fixes. A community digest listed v1.12.0 as the current Haveno tag in late October.

Warning: We couldn’t independently confirm the current trading status of every Haveno network as of this writing. Before trading, check your network’s official announcement channel, run only the latest client, and start with a small amount. Never install a “patched” client from a link in a chat or forum DM.

For step-by-step guidance on using Haveno safely, see our Buy, Sell & Swap section.

THORChain’s native XMR swaps: announced, not yet live

How it is meant to work

THORChain is a cross-chain liquidity network that swaps native assets such as BTC and ETH without wrapped tokens. Adding Monero was hard because of XMR’s privacy. THORChain’s own blog explained on 10 April 2026 that validators outside a vault can’t see Monero outbound transactions without the vault’s private key. Its fix was:

• A single dedicated Asgard vault for XMR with all 100+ active validators as members, so every validator can verify funds independently.
• FROST threshold signing taken from Luke Parker’s Serai project.
• Memoless transactions, because Monero’s 16-byte memo field is too small for swap instructions.
• A small initial pool (about $10,000 at the time) with the treasury as main liquidity provider, and a warning to expect early pauses and bugs.

In April the team estimated mainnet in “1–2 months, closer to two.” That slipped.

Timeline since

1. 25 August 2026: a Chainwire press release announced THORChain 3.20, with native XMR and ZEC swaps against BTC, ETH and stablecoins, no wrapped tokens and no accounts. The release was sponsored content and contained no audit details.
2. 19 October 2026: v3.21.0 hardened XMR key generation and signing after an audit by Least Authority, according to CryptoTicker.
3. 3 and 7 November 2026: v3.21.1 and v3.21.2 shipped. Reports credit v3.21.1 with finishing the Monero development work.
4. 5 November 2026: developer Chad Barraford estimated at least a week, possibly two, before node churn resumed, with delays linked to issues on other chains (Solana and Base).
5. As of 10 November 2026: XMR swaps were not live. A small test pool of a few hundred dollars was expected after the churn, with no timetable for full trading.

Note: “Announced” and “live” are different milestones. Check THORChain’s own status pages, or a front-end’s supported-asset list, before sending XMR anywhere.

The Wagyu data leak (October 2026)

Wagyu is a no-KYC cross-chain swap service. In late October its backend data surfaced publicly:

• 27 October: a ransomware-tracking archive attributed the data to a group called WhiteArmor, which reportedly demanded $5 million.
• 28 October: Hudson Rock published an analysis, and Wagyu’s operator issued a statement.

According to Hudson Rock’s figures, as reported by CryptoTicker on 2 November:

Wagyu said the leak covered about three months, that no funds were lost, and that swaps continued with tightened security. CryptoTicker noted those claims came from the operator and were unverified. Hudson Rock said the data showed no weakness in Monero’s cryptography. Still, because Bitcoin deposits are public, a row that ties a BTC deposit to an XMR address and an IP is a real investigative lead. The more immediate risk for affected users is targeted phishing that quotes accurate order details.

Tip: A no-KYC service can still log your IP, browser fingerprint and timestamps. Use Tor or a trusted VPN when you use swap services, send each swap to a fresh subaddress, and be suspicious of any message that “knows” your order details.

What it means for users

The common thread is that Monero’s on-chain privacy held up in every incident. What failed was software around the chain: a trade protocol’s message validation and a service’s data handling. As EU exchanges prepare to drop privacy coins completely by July 2027 (see our News section), more users will rely on these non-custodial venues. Their security track record matters more each year.