Bitcoin Ordinals extension UniSat Wallet hit by 'large number' of double-spend attacks

Quick Take

  • UniSat Wallet was hit by a wave of double-spend attacks.
  • It promised to refund affected users.

Hours after the open-source Chrome extension for Bitcoin ordinals became inaccessible, UniSat Wallet announced that it was hit by a large number of double-spend attacks resulting from a vulnerability in its codebase.

"During our testing last week, we simulated different approaches to double-spend attacks and made improvements and enhancements to the code," UniSat Wallet explained on Twitter. "Unfortunately, certain problems were still exposed in the initial public version."

A preliminary investigation by the extension's team claims 70 transactions were affected out of 383. 

UniSat Wallet claims to be the first BRC-20 wallet and marketplace provider.

UniSat Wallet claims it will compensate users

UniSat Wallet stated that it will "compensate users who are determined to be associated with the incident for their losses" after further investigations over the next few days.


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It also asked users who believe they were affected to open a support ticket on its Discord server.

"Please understand that BRC-20 is still very young and there have been numerous issues identified and resolved in the past 30 days," UniSat Wallet tweeted.

"As the first BRC-20 wallet provider and the first marketplace provider, UniSat is constantly facing numerous issues and moving forward with your full support," it added.

The BRC-20 token standard is a relatively new and experimental fungible token standard created using Ordinals and Inscriptions. These are saved on the Bitcoin blockchain.

© 2023 The Block. All Rights Reserved. This article is provided for informational purposes only. It is not offered or intended to be used as legal, tax, investment, financial, or other advice.

About Author

Adam is the managing editor for Europe, the Middle East and Africa. He is based in central Europe and was a managing editor and podcast host at the crypto exchange OKX's former research arm, OKX Insights. Before that, he co-founded, which he elevated into one of the leading crypto media brands at its peak as the editor-in-chief. Earlier, he served as the editor-in-chief at Before joining the blockchain and crypto industry, he worked for, and He tweets via @XBT002 and can be emailed at [email protected].


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