Homoglyphs are what?

Homoglyphs are what?

Posted on 27 March 2023
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Homoglyph attacks are a type of cyberattack where attackers use characters that look similar to other characters to trick users into clicking on malicious links or downloading malware. These attacks can be difficult to detect because the characters used are so similar to the real ones. However, there are ways to protect yourself from homoglyph attacks.

One way to protect yourself is to carefully check URLs before clicking on them. Look for subtle differences in characters that could indicate a homoglyph attack, such as the use of a lowercase "l" instead of an uppercase "I." You can also use a browser extension or plugin that can detect homoglyphs and alert you to potential threats.

Another way to protect yourself is to keep your computer's software up to date with the latest security patches and to use antivirus software. This can help prevent malware from being downloaded onto your computer in the first place.

By following these tips, you can make homoglyph attacks less effective and keep your personal information safe online.

Homoglyphs are characters that resemble each other, such as the letter O and zero (‘0’), the Latin letter “H” and the Cyrillic letter “H,” or the uppercase “I” (“I”) and the lowercase letter “l” (L), which look identical in a sans serif font (like Calibri).

In a homoglyph attack (also sometimes called a homograph attack), the threat actor uses homoglyphs to spoof a URL or obfuscate code. For example, the attacker might create a fake URL that spoofs a legitimate URL by using a homoglyph, like “InternationalBank.com,” switching out the letter sans serif letter “I” (“I”) for the lowercase sans serif letter “l” (L). Or the threat actor might use homoglyphs in the malware code to hide nefarious intent by inserting them into code strings that to the naked eye look normal but instead instruct the malware to do something different, like change the code’s perceived intent, such as making an ‘if’ statement always true or redirecting the user to a malicious domain.

Here are some simple examples of homoglyph attacks:

  • Phishing Scams: An attacker sends an email that appears to be from a trusted source (such as a bank or social media platform) asking the recipient to click on a link to verify their account details. However, the link contains a homoglyph that makes it look like it leads to the legitimate website, when in fact it redirects to a malicious site where the attacker can steal the user's login credentials.
  • Malware: A hacker inserts a homoglyph into the code of a legitimate-looking software application that the victim downloads from an untrustworthy website. The homoglyph could be used to bypass security checks or to make the malware more difficult to detect by antivirus software.
  • Spoofing: An attacker creates a website that imitates a well-known brand or organization, using homoglyphs in the URL to make it appear authentic. For example, they might use the letter 'rn' (rn) instead of 'm' to make the domain name look like the real one, such as "Gooqle.com" instead of "Google.com". Users who enter their login details or personal information on the fake site can unknowingly provide it to the attacker.
By:Scott Tunn

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