Tangem Wallet Pack of 2 - Secure Crypto Wallet - Trusted Cold Storage for Bitcoin, Ethereum, NFT's &

Tangem Wallet Pack of 2 - Secure Crypto Wallet - Trusted Cold Storage for Bitcoin, Ethereum, NFT's &
Key item features Ultimate Security: Generates a private key that remains on the card, safeguarding crypto and NFTs from hackers with EAL6+ certification and audited firmware. Versatile Compatibility: Manages over 13,000 tokens across 70+ blockchains, supporting DeFi, NFTs, and DeEx without wires, Bluetooth, or USB. Effortless Operation: Utilizes NFC for secure transactions via a mobile device and the Tangem app, enabling buying and selling crypto with various payment methods. Smart Backup: Features a second Tangem Wallet as a backup, eliminating the need for paper, pictures, or seed phrases for recovery. Durable Design: Boasts IP68 protection against environmental conditions, ensuring longevity and robust physical security. Comprehensive Support: Compatible with Bitcoin, Ethereum, Solana, XRP, USDT, and over 6,000 cryptocurrencies, integrating with dApps and WalletConnect.

LBANK

LBANK

Does OP_CHECKSIGFROMSTACK intentionally allow cross-UTXO signature reuse?

I ran a CSFS experiment on Bitcoin Inquisition Signet and got a spend confirmed:

https://mempool.space/signet/tx/cc1b6d352f75348b6a52c7f5c68fc5caea2512423e08011e8f69a9bb85195f97

The tapscript is simply:

<pubkey> OP_CHECKSIGFROMSTACK

The witness provides (sig, msg, script, control_block).

Since (sig, msg) becomes public after spending, if another UTXO is later sent to the same script, anyone could reuse the exact same pair to spend it — because CSFS only enforces:

schnorr_verify(pubkey, msg, sig)

with no commitment to the spending transaction. By contrast, OP_CHECKSIG signatures commit to the input outpoint, so cross-UTXO reuse is impossible.

This leads to three questions:

  1. Is cross-UTXO signature reuse an intentional property of CSFS, or a risk that must be handled at the script level?
  2. What are the standard patterns to prevent unintended reuse — include the outpoint in msg? combine with OP_CHECKSIG?
  3. In oracle constructions where reuse is desirable (e.g., attesting "BTC > 100k"), is this the intended security model?


from Recent Questions - Bitcoin Stack Exchange https://ift.tt/DjpRtOn
via IFTTT

Popular posts from this blog

Crypto Exec Warns Tokenization Is Moving Faster Than Expected

Image
According to a post shared on X by Keith Grossman, president of crypto payments firm MoonPay, finance is heading toward an onchain future that could unfold over several years. The view comes as large banks and asset managers begin product tokenization, a move that once seemed extreme but is now being treated as a practical step by major institutions. Regulatory Signals Push Institutions Forward Based on reports cited by Grossman, progress has accelerated because rules are becoming clearer. Legislative efforts, regulatory guidance, bank involvement and accounting standards are starting to line up. That combination reduces uncertainty, which is often what slows large pools of capital. BlackRock has already launched tokenized funds, while Franklin Templeton is running tokenized money market funds on public blockchains. Those actions suggest that tokenization is no longer confined to pilot labs or internal trials. It is being used with real assets and real clients. Bank of Ameri...
Read more

Bitcoin Mining Could Be Strengthening The Ruble, Russian Central Bank Says

Image
Bitcoin mining may be providing incremental support to the Russian ruble, Central Bank Governor Elvira Nabiullina said, while cautioning that the effect is difficult to measure because much of the sector still operates in a legal and reporting gray zone. Bitcoin Mining May Support The Ruble Responding to a question at a press conference, Nabiullina said it is “probably difficult to quantify” mining’s influence “because a significant part of mining is still in a gray area.” Still, she added that mining is “indeed one of the additional factors contributing to the strong ruble exchange rate.” As Russian business news portal for RBC reported , her remarks come as Russian officials increasingly frame mining and crypto flows as macro-relevant, not just a niche tech or energy story. Earlier, Maxim Oreshkin, deputy head of the presidential administration, said ruble forecasts have been thrown off by the underestimation of financial flows tied to mining and cryptocurrency. In his view, the s...
Read more

Nigerian SEC Partners With Police To Tackle Crypto Ponzi Schemes – Details

Image
The Nigerian Securities and Exchange Commission (SEC) is maintaining an intense focus on the local cryptocurrency industry, as indicated by recent developments. While introducing minimum capital requirements for previously unregulated virtual asset service providers (VASPs), the securities regulator has also formed an alliance with the Nigeria Police Force (NPF) against cryptocurrency fraud, among other illegal operations. Nigerian SEC Looks To Improve Crypto Investors’ Protection According to local media Voice of Nigeria , the SEC is ramping up efforts aimed at investor protection and transparent market operations in the crypto ecosystem. In a recent meeting with the NPF, the Commission’s Director-General (DG), Dr. Emomotimi Agama, communicated to the Inspector General of Police (IGP), Kayode Egbetokun, concerns over malicious actors in the financial markets who exploit investors’ trust for personal gains.  Dr. Agama said: They cloak their deceit in the glamorous but misunder...
Read more