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Preview of PunyGuard

PunyGuard by Dolan

Local-first protection against IDN homograph attacks, lookalike domains, and phishing script spoofing.

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About this extension
PunyGuard warns you about lookalike domains before you click them.

Attackers register web addresses that look exactly like sites you trust by swapping Latin letters for identical-looking Cyrillic or Greek ones, or by hiding them in Punycode (xn--) form. PunyGuard checks every link, script, frame, and form on the page you are viewing and flags these impostors.

What it does
- Scans every hostname on the page, including embedded links, scripts, and iframes
- Detects homoglyphs, mixed scripts (for example Latin + Cyrillic), invisible characters, and Punycode
- Shows a red, amber, or green badge with the number of risky domains
- Explains each verdict: the Unicode form you see, the real ASCII form, and why it was flagged
- Unicode inspector: every character's U+ code point, official name, block, script, and escapes

Private by design
- All analysis runs on your device; PunyGuard makes no network requests
- No accounts, analytics, tracking, or data collection
- Open source: https://github.com/0xdolan/PunyGuard

Learn how homograph attacks work: https://github.com/0xdolan/PunyGuard/blob/main/docs/README.md
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Permissions and data

Required permissions:

  • Access browser tabs
  • Access your data for all websites

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
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Version
0.2.1
Size
868.57 KB
Last updated
19 days ago (Oct 25, 2026)
Related Categories
  • Privacy & Security
License
Custom License
Privacy Policy
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Version History
  • See all versions
Tags
  • anti malware
  • anti tracker
  • antivirus
  • privacy
  • search
  • security
  • vpn
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