On November 1, 2026, attackers exploited a vulnerability in BTCPay Server versions 2.4.1 and earlier to compromise self-hosted installations and steal BTC and LTC from their hot wallets. The vulnerability had been patched in version 2.4.2 in August, but outdated installations remained exposed. BTCPay Server urged affected operators to take their servers offline, migrate to fresh installations, replace compromised wallet seeds, and rotate potentially exposed credentials. Wallets whose spending keys were held off-server, including hardware wallets, were unaffected

BTCPay Server reported that hot wallets on multiple instances are being swept by unauthorized attackers. The project urgently advised all operators to shut down their instances immediately using ./btcpay-down.sh until the investigation is complete.