ENS Spoofing Bot

ENS Spoofing Bot detects attacks in which someone registers a name visually similar to an existing one.

Forta Protocol, which monitors blockchain events in real-time, together with this bot allows attacks to be detected before they happen or to minimize the damage from them. What's more, every ENS user will be able to receive an alert if it happened to their name.

https://explorer.forta.network/bot/0x907254168eec2d601d2dc097e1dda89c80bbabb9d961c30bdf1eeeaa556dd99e

Table of spoofing techniques supported by the bot.

The problem

Names in the Ethereum Name Service are unique, but there are no restrictions on registering look-alike names that are visually very difficult to distinguish from genuine ones. For example, having a name vitalik.eth, an attacker can register a similar name by replacing the symbol lowercase L with uppercase i: vitaIik.eth. The name is visually similar, but it is treated by the protocol as a completely different name, with its own hash, as well as an address bound to it.

This type of attack is called a homograph attack. Regarding the ENS protocol, it can be performed in the following ways:

• Substitution of character pairs i/I, i/j, O/0, w/vv, m/rn, which depending on the typeface, may be difficult or impossible to distinguish;
• Replacing ascii characters with visually similar ones from Unicode; for example, “faсebooсk.eth” uses the letters o and с from Cyrillic;
• Use of invisible Unicode characters;
• Spoofing using uppercase letters; for example, bitcoin.eth may be spoofed as Bitcoin.eth.

ENS fights this attack pretty hard by normalizing names before they are registered, as well as warning against using non-ascii characters on its site. However, to save gas, such checks have been implemented off-chain, on the frontend side. Any user can register a name bypassing the official site by calling the protocol contract directly.

Spoofing Techniques

Below you will find examples of spoofing techniques that can be detected by this bot.

Original name	Spoofing name	Technique
bitcoin.eth	Bitcoin.eth	Uppercase
danger.eth	dаnger.eth	Cyrillic Homoglyph
glukk.eth	glükk.eth	Unicode Homoglyph
wildcat.eth	w1ldcat.eth	ASCII Homoglyph
vitalik.eth	vitalik​.eth	Zero Width Space
wildcat100	vv1lḍCatl00	Multiple Techniques

Supported Chains

• Ethereum (1)

Alerts

• AK-ENS-SPOOFING-ETH
  • Fired when a transaction contains registration of a name that visually similar to an existing one
  • Severity is always set to "low"
  • Type is always set to "suspicious"
  • Metadata:
    • originalName - the name of the account that was potentially spoofed
    • originalAccount - the address of the account that was potentially spoofed
    • impersonatingName - the name of the account that registered a name similar to the one that already exists
    • impersonatingAccount - the address of the account that registered a name similar to the one that already exists

Test Data

No data yet