A homoglyph attack or homoglyph obfuscation is an anti-analysis, anti-forensics, and deception technique used by malware authors, threat actors, and other such miscreants in which they use similar-looking characters (glyphs) in filenames, variables, urls, etc to blend in with the victim system.
For example, an attacker may register a phishing domain “Iegit[.]com” (uppercase I instead of lowercase l), or name their malware “.X1l” instead of “.X11” (lowercase l instead of numeric 1), or svch0st.exe, …