30 November 2021
Live since
KYC required
Maximum bounty

Program Overview

Blank is the most private, non-custodial Ethereum browser wallet. Blank uses smart contracts that allow users to hide the amounts and origins of cryptocurrency held, in a decentralized and frictionless manner. Each time you want to make a withdrawal, Blank will create a new wallet address for you with the amount of crypto that you requested, which originates from the smart contract where everyone’s funds are pooled.

For more information about Blank, please visit https://www.goblank.io/.
This bug bounty program is focused on their app and is focused on preventing:

  • Thefts of funds of any amount
  • Leak of user data
  • Deletion of user data
  • Access to sensitive pages without authorization

Rewards by Threat Level

Rewards are distributed according to the impact of the vulnerability based on the Immunefi Vulnerability Severity Classification System. This is a simplified 5-level scale, with separate scales for websites/apps and smart contracts/blockchains, encompassing everything from consequence of exploitation to privilege required to likelihood of a successful exploit.

All app bug reports must come with a PoC in order to be considered for a reward. All Medium and Low app bug reports require a suggestion for a fix to be eligible for a reward.

The following vulnerabilities are not eligible for a reward:

  • Any vulnerability that can only be abused by a local attacker
  • Local Attackers (with access to the user’s machine/browser) are not part of our threat model

Bug reports involving the ability to correctly determine the seed phrase will be paid at USD 150 000. All other extension bugs that are critical and result in loss of funds are paid at USD 50 000. High, Medium, and Low Web/App bug reports have the final reward determined by the Blank team depending on exploitability, final impact, and ease of attack.

Payouts are handled by the Blank team directly and are denominated in USD. However, payouts are done in USDC.

Web and Apps

Up to USD $150,000
Up to USD $10,000
Up to USD $1,500
Up to USD $500

Assets in Scope

All repositories of the Blank wallet can be found at Blank · GitHub





However, only those in the Assets in Scope table are considered as in-scope of the bug bounty program.

Impacts in Scope

Only the following impacts are accepted within this bug bounty program. All other impacts are not considered as in-scope, even if they affect something in the assets in scope table.


  • Thefts of funds of any amount
  • Leak of user data
  • Deletion of user data
  • Access to sensitive data without authorization

Prioritized Vulnerabilities

We are especially interested in receiving and rewarding vulnerabilities of the following types:


  • Remote Code Execution
  • Trusting trust/dependency vulnerabilities
  • Vertical Privilege Escalation
  • Horizontal Privilege Escalation
  • Stored XSS
  • Reflective XSS with impact
  • CSRF with impact
  • Direct object reference
  • Internal SSRF
  • Session fixation
  • Insecure Deserialization
  • SSL misconfigurations
  • SSL/TLS issues (weak crypto, improper setup)
  • URL redirect
  • Clickjacking (must be accompanied with PoC)
  • Misleading Unicode text (e.g. using right to left override characters)

Out of Scope & Rules

The following vulnerabilities are excluded from the rewards for this bug bounty program:

  • Attacks that the reporter has already exploited themselves, leading to damage
  • Attacks requiring access to leaked keys/credentials
  • Attacks requiring access to privileged addresses (governance, strategist)
  • Attacks that require access to the user's machine or browser, physical or remote


  • Theoretical vulnerabilities without any proof or demonstration
  • Content spoofing / Text injection issues
  • Self-XSS
  • Captcha bypass using OCR
  • CSRF with no security impact (logout CSRF, change language, etc.)
  • Missing HTTP Security Headers (such as X-FRAME-OPTIONS) or cookie security flags (such as “httponly”)
  • Server-side information disclosure such as IPs, server names, and most stack traces
  • Vulnerabilities used to enumerate or confirm the existence of users or tenants
  • Vulnerabilities requiring unlikely user actions
  • URL Redirects (unless combined with another vulnerability to produce a more severe vulnerability)
  • Lack of SSL/TLS best practices
  • DDoS vulnerabilities
  • Attacks requiring privileged access from within the organization
  • Feature requests
  • Best practices

The following activities are prohibited by this bug bounty program:

  • Any testing with mainnet or public testnet contracts; all testing should be done on private testnets
  • Any testing with pricing oracles or third party smart contracts
  • Attempting phishing or other social engineering attacks against our employees and/or customers
  • Any testing with third party systems and applications (e.g. browser extensions) as well as websites (e.g. SSO providers, advertising networks)
  • Any denial of service attacks
  • Automated testing of services that generates significant amounts of traffic
  • Public disclosure of an unpatched vulnerability in an embargoed bounty