Here’s what happened in crypto today

Today in crypto, Strategy sold 1,690 Bitcoin to repurchase STRC shares, boosting its US dollar reserve to $4.65 billion and reducing its Bitcoin holdings to 840,447 BTC. Meanwhile, concerns over security and regulation dominated the agenda as a blockchain founder warned the first quantum-powered crypto attack may be indistinguishable from an ordinary wallet breach and BTCPay Server tightened Lightning access after a critical exploit.

Strategy turns 1,690 BTC into $108.6M STRC buyback

Strategy, which holds the largest corporate Bitcoin treasury, sold BTC for the second week in a row to repurchase its STRC preferred stock.

The company sold 1,690 Bitcoin for $108.6 million between Aug. 3 and Aug. 9, according to a Monday 8-K filing with the US Securities and Exchange Commission (SEC).

Strategy used the proceeds to buy back 1.15 million shares of its STRC preferred stock for $108.6 million. STRC is a variable-rate preferred stock designed to pay monthly dividends.

The transaction marked Strategy’s fourth disclosed Bitcoin sale of 2026, bringing its total Bitcoin sales for the year to 6,948 BTC, while the company still holds 840,447 BTC purchased for an aggregate $63.36 billion.

Crypto’s first quantum attack will look like unexplained breach: Quantus founder

The first sign that quantum computing has broken modern cryptography probably won’t be a splashy theft of Satoshi Nakamoto’s dormant Bitcoin. It could just be a wave of unrelated crypto wallet breaches with no trace of how an attacker did it, according to the founder of blockchain startup Quantus. 

“When someone cracks your key, you don’t get a memo saying how they did it,” Christopher Smith, CEO and co-founder of Quantus Network, told Cointelegraph. A sufficiently powerful quantum computer could derive a private key from public keys exposed onchain, allowing an attacker to move funds without compromising a wallet, device or exchange’s internal systems. 

This makes the arrival of “Q-day” — a hypothetical future moment when quantum computers become powerful enough to break standard public-key cryptography — unusually difficult to detect. In a theft involving a highly secure organization, “the only forensic evidence would be that there was no breach,” Smith said.

Smith’s warning comes as advances in quantum algorithms have reduced estimates of computing resources needed to attack the elliptic-curve cryptography used by major blockchains. 

BTCPay restricts remote Lightning access after attackers steal funds

BTCPay Server has temporarily restricted public remote connections to Lightning Network nodes running Lightning Network Daemon (LND) software after attackers exploited a critical vulnerability to obtain credentials and move funds. 

BTCPay said the restriction prevents external wallets such as Zeus from connecting through a BTCPay Server domain or Tor onion address on Docker deployments. BTCPay said Lightning payments can continue and that it plans to restore the remote-access option when it considers it safe. 

Version 2.4.2 installs LND version 0.21.1 and automatically regenerates the macaroon credentials on standard BTCPay installations. The project advised operators to check for unauthorized payments, unexpected channel closures, unfamiliar peers and discrepancies in their onchain or Lightning balances.

The BTCPay breach is the latest security incident involving widely used Bitcoin products, following a Coldcard hardware-wallet flaw linked to more than $100 million in confirmed losses. The separate incidents affected software surrounding Bitcoin rather than the network’s underlying protocol.