SlowMist’s Cosine Raises Privacy Questions About Clear Signing Data Collection

Clear signing is intended to help crypto users understand what they are approving before a transaction reaches the blockchain. But the process of turning raw transaction data into a readable prompt can involve software outside the hardware wallet—and that software may handle information users do not expect to share.

On November 11, SlowMist founder Cosine raised concerns about a data-collection mechanism associated with a clear-signing integration. According to his account, the mechanism collects certain signing-related information by default, including the network or chain ID, the destination address, device and software versions, and whether blind signing was used.

The distinction is important: Cosine described the mechanism as part of a software development kit used by wallet applications, not as a feature embedded in device firmware. His account also said that a wallet application connecting to the device would need to provide the relevant control for users to change the setting.

What information may be involved?

The reported fields cover both transaction context and the environment in which a signature is requested:

• Network or chain ID: Identifies the blockchain network associated with the request.
• Destination address: May identify a smart contract or a recipient.
• Device model and software versions: Can describe the device, firmware and application involved.
• Blind-signing status and reason: Indicates whether the request was signed without a fully interpretable display and, if so, why.

These details are not the same as a private key or recovery phrase. The reported collection does not, by itself, establish that either secret was exposed.

They can nevertheless be sensitive. A contract address may reveal which protocol a person intends to use, while a recipient address can provide context about a payment. Combined with timing or other information available to a service, metadata may make wallet activity easier to correlate.

Blockchain transactions are often publicly visible after submission, but that does not make every piece of signing metadata public. A user may reasonably distinguish between broadcasting a transaction to a network and sharing details of a signing attempt with an application or service.

Clear signing and blind signing serve different purposes

A transaction request is not always easy to interpret from its raw data. Clear signing aims to present meaningful details—such as the action, destination and relevant parameters—in a form a user can review before approving it.

Blind signing is different: the user approves a request that the device cannot fully interpret or display in a meaningful way. This can arise when a wallet or device lacks the context needed to decode a particular interaction.

The Ethereum transaction documentation explains the basic fields involved in Ethereum transactions. For more complex interactions, however, understanding the destination alone may not be enough. A contract call can grant an allowance or trigger behavior that requires additional context.

Clear signing can improve transaction review, but a readable prompt is not a guarantee that an interaction is safe. Users should still check the application they are using, the requested action and any spending permissions.

Why the application layer matters

A hardware wallet protects signing keys, but users typically interact with it through a wallet application, browser extension or other software. That application may use third-party components to interpret transaction data or communicate with external services.

The reported mechanism illustrates why security and privacy assessments need to cover the full signing flow:

1. A user initiates an action in an application.
2. The application prepares a signing request and may use supporting software to interpret it.
3. The hardware wallet presents information for approval and signs if the user confirms.
4. The application may then submit the signed transaction to the network.

If data collection occurs in software used by the application, changing device settings alone may not control it. Users may instead need a setting in the connected wallet—or an explanation from its developer about what is collected and how to opt out.

The available account does not establish that every wallet using such software collects the same information, nor does it establish how any collected data is retained or combined with other records. Those details depend on the particular integration and its privacy practices.

How to review your signing privacy

Users do not need to give up readable transaction prompts to take privacy seriously. A practical review can cover both what appears on the device and what the connected software does:

• Check wallet privacy settings. Look for controls covering analytics, diagnostics, transaction simulation or external data services.
• Read the application’s disclosures. Pay attention to what data is sent, who receives it, how long it is retained and whether opting out affects functionality.
• Review the device screen before confirming. Compare the network, destination, amount and action with what you intended.
• Treat blind signing as a higher-risk decision. If you cannot understand the request, pause and investigate before approving it.
• Review token allowances periodically. An approval can give a contract permission to spend tokens later; it is not necessarily a one-time transfer.
• Keep software current. Updates can improve security and transaction interpretation, though they may also change features or privacy settings worth reviewing.

The broader takeaway

The key question is not whether clear signing is useful—it can make crypto transactions easier to evaluate. The question is whether users have enough visibility and control over the information exchanged to provide that experience.

For anyone choosing a crypto wallet or connected application, private-key protection is only one part of the decision. Transaction transparency, understandable consent and accessible privacy controls matter too.